Kliknij ten link, aby zobaczyć inne rodzaje publikacji na ten temat: Phonon Liquid Electron Crystal.
Artykuły w czasopismach na temat „Phonon Liquid Electron Crystal”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Sprawdź 50 najlepszych artykułów w czasopismach naukowych na temat „Phonon Liquid Electron Crystal”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Przeglądaj artykuły w czasopismach z różnych dziedzin i twórz odpowiednie bibliografie.
1
Zhang, Wenjie, Chong Zheng, Yanbing Dong, Jia-Yue Yang i Linhua Liu. "Anharmonic phonon frequency and ultralow lattice thermal conductivity in β-Cu2Se liquid-like thermoelectrics". Physical Chemistry Chemical Physics 22, nr 48 (2020): 28086–92. http://dx.doi.org/10.1039/d0cp04591h.
Pełny tekst źródła
2
Singh, D. P., V. Kumar, A. Kumar, R. Manohar, Renu Pasricha, B. Duponchel, Y. Boussoualem, A. H. Sahraoui i A. Daoudi. "Effect of graphene oxide interlayer electron-phonon coupling on the electro-optical parameters of a ferroelectric liquid crystal". RSC Advances 7, nr 21 (2017): 12479–85. http://dx.doi.org/10.1039/c6ra25126a.
Pełny tekst źródłaStreszczenie:
Electro-optical properties of FLC are cell thickness dependent. Interlayer electron-phonon coupling is responsible for the change in the E-O properties. The FLC–GO composite is suitable for use in UV filters.
3
Miyata, Kiyoshi, Timothy L. Atallah i X. Y. Zhu. "Lead halide perovskites: Crystal-liquid duality, phonon glass electron crystals, and large polaron formation". Science Advances 3, nr 10 (październik 2017): e1701469. http://dx.doi.org/10.1126/sciadv.1701469.
Pełny tekst źródła
4
Patel, Piyush, Manisha Patel, Sandip M. Vyas, Maunik P. Jani i Girish R. Pandya. "Single Crystal Growth of Bi:Sb Alloys". Solid State Phenomena 209 (listopad 2013): 173–76. http://dx.doi.org/10.4028/www.scientific.net/ssp.209.173.
Pełny tekst źródłaStreszczenie:
The solid-liquid interface of Bi (1-x) Sb(x) crystal growth is most favorable for investigation of electron and phonon phenomena. Bismuth is a semimetal with high electron and hole mobility. Interest in Bi-Sb material system has recently been stimulated by promise of a new generation of thermoelectric materials based on these alloy. The crystals were grown using zone melting method with 1.0 and 1.5 cm/hour growth velocity and temperature gradient 650C/cm. The surface was determinal on the basis of growth feature profiles under optical microscope. The features observed on the top-free surface of as-grown crystals have also been discussed. The crystals have been characterized by using the powder XRD technique. The optical absorption was measured in the wave number range 510 cm-1 to 4000 cm-1. From the optical absorption through direct inter band transition.The results are reported and discussed in detailed.
5
Магарян, К. А., К. Р. Каримуллин, И. А. Васильева i А. В. Наумов. "Анализ температурной зависимости спектров экситонной люминесценции квантовых точек селенида кадмия, выращенных в жидкокристаллической матрице-=SUP=-*-=/SUP=-". Журнал технической физики 126, nr 1 (2019): 50. http://dx.doi.org/10.21883/os.2019.01.47052.283-18.
Pełny tekst źródłaStreszczenie:
AbstractThe temperature dependences of the positions of maxima of exciton bands in the luminescence spectra of liquid crystal nanocomposites with CdSe quantum dots with sizes of 1.8 and 2.3 nm at T = 77–300 K have been analyzed. The analysis under the theoretical model taking into account the electron–phonon interaction inside quantum dots has made it possible to calculate the values of the Huang–Rhys factor and average phonon energy in nanocrystals under study.
6
Syvokon, V. E., Yu Z. Kovdrya i K. A. Nasyedkin. "Nonlinear Features of Phonon–Ripplon Modes in the Electron Crystal Over Liquid Helium". Journal of Low Temperature Physics 144, nr 1-3 (18.11.2006): 35–48. http://dx.doi.org/10.1007/s10909-006-9223-7.
Pełny tekst źródła
7
Woliński, Tomasz, Sławomir Ertman, Katarzyna Rutkowska, Daniel Budaszewski, Marzena Sala-Tefelska, Miłosz Chychłowski, Kamil Orzechowski, Karolina Bednarska i Piotr Lesiak. "Photonic Liquid Crystal Fibers – 15 years of research activities at Warsaw University of Technology". Photonics Letters of Poland 11, nr 2 (1.07.2019): 22. http://dx.doi.org/10.4302/plp.v11i2.907.
Pełny tekst źródłaStreszczenie:
Research activities in the area of photonic liquid crystal fibers carried out over the last 15 years at Warsaw University of Technology (WUT) have been reviewed and current research directions that include metallic nanoparticles doping to enhance electro-optical properties of the photonic liquid crystal fibers are presented. Full Text: PDF ReferencesT.R. Woliński et al., "Propagation effects in a photonic crystal fiber filled with a low-birefringence liquid crystal", Proc. SPIE, 5518, 232-237 (2004). CrossRef F. Du, Y-Q. Lu, S.-T. Wu, "Electrically tunable liquid-crystal photonic crystal fiber", Appl. Phys. Lett. 85, 2181-2183 (2004). CrossRef T.T. Larsen, A. Bjraklev, D.S. Hermann, J. Broeng, "Optical devices based on liquid crystal photonic bandgap fibres", Opt. Express, 11, 20, 2589-2596 (2003). CrossRef T.R. Woliński et al., "Tunable properties of light propagation in photonic liquid crystal fibers", Opto-Electron. Rev. 13, 2, 59-64 (2005). CrossRef M. Chychłowski, S. Ertman, T.R. Woliński, "Splay orientation in a capillary", Phot. Lett. Pol. 2, 1, 31-33 (2010). CrossRef T.R. Woliński et al., "Photonic liquid crystal fibers — a new challenge for fiber optics and liquid crystals photonics", Opto-Electron. Rev. 14, 4, 329-334 (2006). CrossRef T.R. Woliński et al., "Influence of temperature and electrical fields on propagation properties of photonic liquid-crystal fibres", Meas. Sci. Technol. 17, 985-991 (2006). CrossRef T.R. Woliński et al., "Photonic Liquid Crystal Fibers for Sensing Applications", IEEE Trans. Inst. Meas. 57, 8, 1796-1802 (2008). CrossRef T.R. Woliński, et al., "Multi-Parameter Sensing Based on Photonic Liquid Crystal Fibers", Mol. Cryst. Liq. Cryst. 502: 220-234., (2009). CrossRef T.R. Woliński, Xiao G and Bock WJ Photonics sensing: principle and applications for safety and security monitoring, (New Jersey, Wiley, 147-181, 2012). CrossRef T.R. Woliński et al., "Propagation effects in a polymer-based photonic liquid crystal fiber", Appl. Phys. A 115, 2, 569-574 (2014). CrossRef S. Ertman et al., "Optofluidic Photonic Crystal Fiber-Based Sensors", J. Lightwave Technol., 35, 16, 3399-3405 (2017). CrossRef S. Ertman et al., "Recent Progress in Liquid-Crystal Optical Fibers and Their Applications in Photonics", J. Lightwave Technol., 37, 11, 2516-2526 (2019). CrossRef M.M. Tefelska et al., "Electric Field Sensing With Photonic Liquid Crystal Fibers Based on Micro-Electrodes Systems", J. Lightwave Technol., 33, 2, 2405-2411, (2015). CrossRef S. Ertman et al., "Index Guiding Photonic Liquid Crystal Fibers for Practical Applications", J. Lightwave Technol., 30, 8, 1208-1214 (2012). CrossRef K. Mileńko, S. Ertman, T. R. Woliński, "Numerical analysis of birefringence tuning in high index microstructured fiber selectively filled with liquid crystal", Proc. SPIE - The International Society for Optical Engineering, 8794 (2013). CrossRef O. Jaworska and S. Ertman, "Photonic bandgaps in selectively filled photonic crystal fibers", Phot. Lett. Pol., 9, 3, 79-81 (2017). CrossRef I.C. Khoo, S.T.Wu, "Optics and Nonlinear Optics of Liquid Crystals", World Scientific (1993). CrossRef P. Lesiak et al., "Thermal optical nonlinearity in photonic crystal fibers filled with nematic liquid crystals doped with gold nanoparticles", Proc. SPIE 10228, 102280N (2017). CrossRef K. Rutkowska, T. Woliński, "Modeling of light propagation in photonic liquid crystal fibers", Photon. Lett. Poland 2, 3, 107 (2010). CrossRef K. Rutkowska, L-W. Wei, "Assessment on the applicability of finite difference methods to model light propagation in photonic liquid crystal fibers", Photon. Lett. Poland 4, 4, 161 (2012). CrossRef K. Rutkowska, U. Laudyn, P. Jung, "Nonlinear discrete light propagation in photonic liquid crystal fibers", Photon. Lett. Poland 5, 1, 17 (2013). CrossRef M. Murek, K. Rutkowska, "Two laser beams interaction in photonic crystal fibers infiltrated with highly nonlinear materials", Photon. Lett. Poland 6, 2, 74 (2014). CrossRef M.M. Tefelska et al., "Photonic Band Gap Fibers with Novel Chiral Nematic and Low-Birefringence Nematic Liquid Crystals", Mol. Cryst. Liq. Cryst., 558, 184-193, (2012). CrossRef M.M. Tefelska et al., "Propagation Effects in Photonic Liquid Crystal Fibers with a Complex Structure", Acta Phys. Pol. A, 118, 1259-1261 (2010). CrossRef K. Orzechowski et al., "Polarization properties of cubic blue phases of a cholesteric liquid crystal", Opt. Mater. 69, 259-264 (2017). CrossRef H. Yoshida et al., "Heavy meson spectroscopy under strong magnetic field", Phys. Rev. E 94, 042703 (2016). CrossRef J. Yan et al., "Extended Kerr effect of polymer-stabilized blue-phase liquid crystals", Appl. Phys. Lett. 96, 071105 (2010). CrossRef C.-W. Chen et al., "Random lasing in blue phase liquid crystals", Opt. Express 20, 23978-23984 (2012). CrossRef C.-H. Lee et al., "Polarization-independent bistable light valve in blue phase liquid crystal filled photonic crystal fiber", Appl. Opt. 52, 4849-4853 (2013). CrossRef D. Poudereux et al., "Infiltration of a photonic crystal fiber with cholesteric liquid crystal and blue phase", Proc. SPIE 9290 (2014). CrossRef K. Orzechowski et al., "Optical properties of cubic blue phase liquid crystal in photonic microstructures", Opt. Express 27, 10, 14270-14282 (2019). CrossRef M. Wahle, J. Ebel, D. Wilkes, H.S. Kitzerow, "Asymmetric band gap shift in electrically addressed blue phase photonic crystal fibers", Opt. Express 24, 20, 22718-22729 (2016). CrossRef K. Orzechowski et al., "Investigation of the Kerr effect in a blue phase liquid crystal using a wedge-cell technique", Phot. Lett. Pol. 9, 2, 54-56 (2017). CrossRef M.M. Sala-Tefelska et al., "Influence of cylindrical geometry and alignment layers on the growth process and selective reflection of blue phase domains", Opt. Mater. 75, 211-215 (2018). CrossRef M.M. Sala-Tefelska et al., "The influence of orienting layers on blue phase liquid crystals in rectangular geometries", Phot. Lett. Pol. 10, 4, 100-102 (2018). CrossRef P. G. de Gennes JP. The Physics of Liquid Crystals. (Oxford University Press 1995). CrossRef L.M. Blinov and V.G. Chigrinov, Electrooptic Effects in Liquid Crystal Materials (New York, NY: Springer New York 1994). CrossRef D. Budaszewski, A.J. Srivastava, V.G. Chigrinov, T.R. Woliński, "Electro-optical properties of photo-aligned photonic ferroelectric liquid crystal fibres", Liq. Cryst., 46 2, 272-280 (2019). CrossRef V. G. Chigrinov, V. M. Kozenkov, H-S. Kwok. Photoalignment of Liquid Crystalline Materials (Chichester, UK: John Wiley & Sons, Ltd 2008). CrossRef M. Schadt et al., "Surface-Induced Parallel Alignment of Liquid Crystals by Linearly Polymerized Photopolymers", Jpn. J. Appl. Phys.31, 2155-2164 (1992). CrossRef D. Budaszewski et al., "Photo-aligned ferroelectric liquid crystals in microchannels", Opt. Lett. 39, 4679 (2014). CrossRef D. Budaszewski, et al., "Photo‐aligned photonic ferroelectric liquid crystal fibers", J. Soc. Inf. Disp. 23, 196-201 (2015). CrossRef O. Stamatoiu, J. Mirzaei, X. Feng, T. Hegmann, "Nanoparticles in Liquid Crystals and Liquid Crystalline Nanoparticles", Top Curr Chem 318, 331-392 (2012). CrossRef A. Siarkowska et al., "Titanium nanoparticles doping of 5CB infiltrated microstructured optical fibers", Photonics Lett. Pol. 8 1, 29-31 (2016). CrossRef A. Siarkowska et al., "Thermo- and electro-optical properties of photonic liquid crystal fibers doped with gold nanoparticles", Beilstein J. Nanotechnol. 8, 2790-2801 (2017). CrossRef D. Budaszewski et al., "Nanoparticles-enhanced photonic liquid crystal fibers", J. Mol. Liq. 267, 271-278 (2018). CrossRef D. Budaszewski et al., "Enhanced efficiency of electric field tunability in photonic liquid crystal fibers doped with gold nanoparticles", Opt. Exp. 27, 10, 14260-14269 (2019). CrossRef
8
Orzechowski, Kamil, Marek Wojciech Sierakowski, Marzena Sala-Tefelska, Tomasz Ryszard Woliński, Olga Strzeżysz i Przemysław Kula. "Investigation of Kerr effect in a blue phase liquid crystal using wedge-cell technique". Photonics Letters of Poland 9, nr 2 (1.07.2017): 54. http://dx.doi.org/10.4302/plp.v9i2.738.
Pełny tekst źródłaStreszczenie:
In this work an alternative method for refractive index measurement of blue phase liquid crystal in the Kerr effect has been described. The proposed wedge method uses simple goniometric setup, allowing for direct index measurements for any wavelengths and index values. This is significant advantage comparing to other methods, usually having limitations of the measurement range as well as necessity complicated calculation to obtain refractive indices values. The results are reliable and agree well with the subject literature. Full Text: PDF ReferencesW. Cao et al., "Lasing in a three-dimensional photonic crystal of the liquid crystal blue phase II", Nat. Mater. 1, 111-113 (2002). CrossRef S. Meiboom, M. Sammon, W.F. Brinkman, "Lattice of disclinations: The structure of the blue phases of cholesteric liquid crystals", Phys. Rev. A. 27, 438 (1983). CrossRef S. Tanaka et al., "Double-twist cylinders in liquid crystalline cholesteric blue phases observed by transmission electron microscopy", Sci. Rep. 5, 16180 (2015). CrossRef Y. Li and S.-T. Wu, "Polarization independent adaptive microlens with a blue-phase liquid crystal", Opt. Express 19(9), 8045-8050 (2011). CrossRef N. Rong et al., "Polymer-Stabilized Blue-Phase Liquid Crystal Fresnel Lens Cured With Patterned Light Using a Spatial Light Modulator", J. of Disp. Technol. 12(10), 1008-1012 (2016). CrossRef J.-D. Lin et al., "Spatially tunable photonic bandgap of wide spectral range and lasing emission based on a blue phase wedge cell", Opt. Express 22(24), 29479-29492 (2014). CrossRef P. Joshi et al., "Tunable light beam steering device using polymer stabilized blue phase liquid crystals", Photon. Lett. Poland 9(1), 11-13 (2017). CrossRef Ch.-W. Chen et al., "Temperature dependence of refractive index in blue phase liquid crystals", Opt. Mater. Express 3(5), 527-532 (2013). CrossRef Y.-H. Lin et al., "Measuring electric-field-induced birefringence in polymer stabilized blue-phase liquid crystals based on phase shift measurements", J. Appl. Phys. 109, 104503 (2011). CrossRef J. Yan et al., "Direct measurement of electric-field-induced birefringence in a polymer-stabilized blue-phase liquid crystal composite", Opt. Express 18(11), 11450-11455 (2010). CrossRef K.A. Rutkowska, K. Orzechowski, M. Sierakowski, "Wedge-cell technique as a simple and effective method for chromatic dispersion determination of liquid crystals", Photon. Lett. Poland 8(2), 51-53 (2016). CrossRef O. Chojnowska et al., "Electro-optical properties of photochemically stable polymer-stabilized blue-phase material", J. Appl. Phys. 116, 213505 (2014). CrossRef J. Yan et al., "Extended Kerr effect of polymer-stabilized blue-phase liquid crystals", Appl. Phys. Lett. 96, 071105 (2010). CrossRef M. Chen et al., "Electrically assisting crystal growth of blue phase liquid crystals", Opt. Mater. Express 4(5), 953-959 (2014). CrossRef J. Kerr, Philos. Mag. 50, 337 (1875).
9
Pandey, Juhi, Shriparna Mukherjee, Divya Rawat, Shoeb Athar, Kewal Singh Rana, Ramesh Chandra Mallik i Ajay Soni. "Raman Spectroscopy Study of Phonon Liquid Electron Crystal in Copper Deficient Superionic Thermoelectric Cu2–xTe". ACS Applied Energy Materials 3, nr 3 (27.01.2020): 2175–81. http://dx.doi.org/10.1021/acsaem.9b02317.
Pełny tekst źródła
10
Sivokon’, V. E., V. V. Dotsenko i Yu Z. Kovdrya. "Nonlinear phenomena in phonon–ripplon oscillations in a two-dimensional electron crystal over liquid helium". Low Temperature Physics 27, nr 2 (luty 2001): 83–87. http://dx.doi.org/10.1063/1.1353696.
Pełny tekst źródła
11
Quémerais, P., i S. Fratini. "Polaron Crystallization and the Metal–Insulator Transition". International Journal of Modern Physics B 12, nr 29n31 (20.12.1998): 3131–36. http://dx.doi.org/10.1142/s0217979298002210.
Pełny tekst źródłaStreszczenie:
The Crystallization of polarons at finite density, due to the long-range Coulomb forces — when no bipolarons can be formed — is discussed close to the metal–insulator transition (MIT). As a function of the density, the melting is examined at zero temperature. By calculating the quantum fluctuations of both the electron and the polarization, we show that at strong electron–phonon coupling the dissociation of the polarons at the MIT is favored, rather than the melting towards a polaron liquid. In this regime, we demonstrate, that an instability of the transverse vibrational modes of the polaron crystal occurs as the density increases. This provides a new physical mechanism for the MIT in polar materials, for which an experimental signature is predicted.
12
Xu, Youming, Shucheng Guo i Xi Chen. "Crystal Growth and Thermal Properties of Quasi-One-Dimensional van der Waals Material ZrSe3". Micromachines 13, nr 11 (17.11.2022): 1994. http://dx.doi.org/10.3390/mi13111994.
Pełny tekst źródłaStreszczenie:
ZrSe3 with a quasi-one-dimensional (quasi-1D) crystal structure belongs to the transition metal trichalcogenides (TMTCs) family. Owing to its unique optical, electrical, and optoelectrical properties, ZrSe3 is promising for applications in field effect transistors, photodetectors, and thermoelectrics. Compared with extensive studies of the above-mentioned physical properties, the thermal properties of ZrSe3 have not been experimentally investigated. Here, we report the crystal growth and thermal and optical properties of ZrSe3. Millimeter-sized single crystalline ZrSe3 flakes were prepared using a chemical vapor transport method. These flakes could be exfoliated into microribbons by liquid-phase exfoliation. The transmission electron microscope studies suggested that the obtained microribbons were single crystals along the chain axis. ZrSe3 exhibited a specific heat of 0.311 J g−1 K−1 at 300 K, close to the calculated value of the Dulong–Petit limit. The fitting of low-temperature specific heat led to a Debye temperature of 110 K and an average sound velocity of 2122 m s−1. The thermal conductivity of a polycrystalline ZrSe3 sample exhibited a maximum value of 10.4 ± 1.9 W m−1 K−1 at 40 K. The thermal conductivity decreased above 40 K and reached a room-temperature value of 5.4 ± 1.3 W m−1 K−1. The Debye model fitting of the solid thermal conductivity agreed well with the experimental data below 200 K but showed a deviation at high temperatures, indicating that optical phonons could substantially contribute to thermal transport at high temperatures. The calculated phonon mean free path decreased with temperatures between 2 and 21 K. The mean free path at 2 K approached 3 μm, which was similar to the grain size of the polycrystalline sample. This work provides useful insights into the preparation and thermal properties of quasi-1D ZrSe3.
13
Sharkov, A. I., T. I. Galkina, V. S. Krivobok, A. Yu Klokov, P. V. Shapkin i V. S. Bagaev. "Evolution of phonon nonequilibrium in single-crystal ZnSe at liquid-helium temperatures". Physics of the Solid State 48, nr 9 (wrzesień 2006): 1764–68. http://dx.doi.org/10.1134/s1063783406090265.
Pełny tekst źródła
14
Sales, Brian C. "Electron Crystals and Phonon Glasses: A New Path to Improved Thermoelectric Materials". MRS Bulletin 23, nr 1 (styczeń 1998): 15–21. http://dx.doi.org/10.1557/s0883769400031419.
Pełny tekst źródłaStreszczenie:
In materials that conduct both electricity and heat, the thermal and electrical currents are coupled. This thermoelectric coupling can be used to construct devices that act as temperature sensors, heat pumps, refrigerators, or power generators. A temperature difference ΔT across any electrical conductor will generate a corresponding voltage difference ΔV The ratio ΔV/ΔT is defined as the Seebeck coefficient S after Thomas See-beck who first discovered the effect in 1823. Probably the most familiar use of this effect is the thermocouple in which the union of two dissimilar metals generates a voltage in response to an imposed temperature difference. Interestingly an electrical current I passing through the junction of two dissimilar conductors results in the absorption or release of heat in the vicinity of the junction depending on the direction of the current. The ability to heat or cool in this manner was first discovered by Peltier and explained by Lord Kelvin. The latter showed that the amount of heat produced (or absorbed) near the junction is given by ΠI = STI where Π is called the Peltier coefficient and T is the temperature. It is primarily this effect that makes thermoelectric (Peltier) refrigeration possible. Thermoelectric refrigerators and power generators are attractive for many applications as they have no moving parts (except electrons and holes), use no liquid refrigerant, and last indefinitely.
15
Chen, Ching, Sergey Galitskiy, Avanish Mishra i Avinash M. Dongare. "Modeling laser interactions with aluminum and tantalum targets using a hybrid atomistic-continuum model". Journal of Applied Physics 133, nr 10 (14.03.2023): 105901. http://dx.doi.org/10.1063/5.0138389.
Pełny tekst źródłaStreszczenie:
A hybrid atomistic-continuum method can model the microstructure evolution of metals subjected to laser irradiation. This method combines classical molecular dynamics (MD) simulations with the two-temperature model (TTM) to account for the laser energy absorption and heat diffusion behavior. Accurate prediction of the temperature evolution in the combined MD-TTM method requires reliable accuracy in electron heat capacity, electron thermal conductivity, and electron–phonon coupling factor across the temperatures generated. This study uses the electronic density of states (DOS) obtained from first-principle calculations. The calculated electron temperature-dependent parameters are used in MD-TTM simulations to study the laser metal interactions in FCC and BCC metals and the phenomenon of laser shock loading and melting. This study uses FCC Al and BCC Ta as model systems to demonstrate this capability. When subjected to short pulsed laser shocks, the dynamic failure behavior predicted using temperature-dependent parameters is compared with the experimentally reported single-crystal and nanocrystalline Al and Ta systems. The MD-TTM simulations also investigate laser ablation and melting behavior of Ta to compare with the ablation threshold reported experimentally. This manuscript demonstrates that integrating the temperature-dependent parameters into MD-TTM simulations leads to the accurate modeling of the laser–metal interaction and allows the prediction of the kinetics of the solid–liquid interface.
16
Schubert, Robin, Arne Meyer, Karsten Dierks, Svetlana Kapis, Rudolph Reimer, Howard Einspahr, Markus Perbandt i Christian Betzel. "Reliably distinguishing protein nanocrystals from amorphous precipitate by means of depolarized dynamic light scattering". Journal of Applied Crystallography 48, nr 5 (29.08.2015): 1476–84. http://dx.doi.org/10.1107/s1600576715014740.
Pełny tekst źródłaStreszczenie:
Crystallization of biological macromolecules such as proteins implies several prerequisites, for example, the presence of one or more initial nuclei, sufficient amounts of the crystallizing substance and the chemical potential to provide the free energy needed to force the process. The initiation of a crystallization process itself is a stochastic event, forming symmetrically assembled nuclei over kinetically preferred protein-dense liquid clusters. The presence of a spatial repetitive orientation of macromolecules in the early stages of the crystallization process has so far proved undetectable. However, early identification of the occurrences of unit cells is the key to nanocrystal detection. The optical properties of a crystal lattice offer a potential signal with which to detect whether a transition from disordered to ordered particles occurs, one that has so far not been tested in nanocrystalline applications. The ability of a lattice to depolarize laser light depends on the different refractive indices along different crystal axes. In this study a unique experimental setup is used to detect nanocrystal formation by application of depolarized scattered light. The results demonstrate the successful detection of nano-sized protein crystals at early stages of crystal growth, allowing an effective differentiation between protein-dense liquid cluster formation and ordered nanocrystals. The results are further verified by complementary methods like X-ray powder diffraction, second harmonic generation, ultraviolet two-photon excited fluorescence and scanning electron microscopy.
17
Echelmeier, Austin, Daihyun Kim, Jorvani Cruz Villarreal, Jesse Coe, Sebastian Quintana, Gerrit Brehm, Ana Egatz-Gomez i in. "3D printed droplet generation devices for serial femtosecond crystallography enabled by surface coating". Journal of Applied Crystallography 52, nr 5 (29.08.2019): 997–1008. http://dx.doi.org/10.1107/s1600576719010343.
Pełny tekst źródłaStreszczenie:
The role of surface wetting properties and their impact on the performance of 3D printed microfluidic droplet generation devices for serial femtosecond crystallography (SFX) are reported. SFX is a novel crystallography method enabling structure determination of proteins at room temperature with atomic resolution using X-ray free-electron lasers (XFELs). In SFX, protein crystals in their mother liquor are delivered and intersected with a pulsed X-ray beam using a liquid jet injector. Owing to the pulsed nature of the X-ray beam, liquid jets tend to waste the vast majority of injected crystals, which this work aims to overcome with the delivery of aqueous protein crystal suspension droplets segmented by an oil phase. For this purpose, 3D printed droplet generators that can be easily customized for a variety of XFEL measurements have been developed. The surface properties, in particular the wetting properties of the resist materials compatible with the employed two-photon printing technology, have so far not been characterized extensively, but are crucial for stable droplet generation. This work investigates experimentally the effectiveness and the long-term stability of three different surface treatments on photoresist films and glass as models for our 3D printed droplet generator and the fused silica capillaries employed in the other fluidic components of an SFX experiment. Finally, the droplet generation performance of an assembly consisting of the 3D printed device and fused silica capillaries is examined. Stable and reproducible droplet generation was achieved with a fluorinated surface coating which also allowed for robust downstream droplet delivery. Experimental XFEL diffraction data of crystals formed from the large membrane protein complex photosystem I demonstrate the full compatibility of the new injection method with very fragile membrane protein crystals and show that successful droplet generation of crystal-laden aqueous droplets intersected by an oil phase correlates with increased crystal hit rates.
18
Swaminathan, S., S. Altynov, I. P. Jones, N. J. Zaluzec, D. M. Maher i H. L. Fraser. "Measurement of Debye-Waller factors of silicon as a function of temperature using energy-filtered CBED rocking-curve technique". Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 996–97. http://dx.doi.org/10.1017/s0424820100172711.
Pełny tekst źródłaStreszczenie:
The advantages of quantitative Convergent Beam Electron Diffraction (CBED) method for x-ray structure factor determination have been reviewed by Spence. The CBED method requires accurate values of Debye-Waller (D-W) factors for the estimation of the coefficients of crystal potential of the higher order beams, Vg, the calculation of the absorption potential, V′g using the Einstein model for phonons, and finally the conversion of the fitted values of the coefficients of crystal potential, V″, to x-ray structure factors. Debye-Waller factors are conventionally determined by neutron or x-ray diffraction methods. Because of the difficulties in conducting high temperature neutron and x-ray diffraction experiments, D-W factors are rarely measured at temperatures above room temperature. Debye-Waller factors at high temperatures can be determined by Convergent Beam Electron diffraction (CBED) method using Transmission Electron Microscopy (TEM) employed with a hot stage attachment. Recently Holmestad et al. have attempted to measure the D-W factors by matching the energy-filtered Higher Order Laue Zone (HOLZ) line intensities near liquid nitrogen temperature.
19
KESHELASHVILI, IRAKLI, DOMINIK WERTHMÜLLER i LILIAN WITTHAUER. "QUASI-FREE PHOTOPRODUCTION OF η-MESONS OFF 2H AND 3He". International Journal of Modern Physics: Conference Series 26 (styczeń 2014): 1460114. http://dx.doi.org/10.1142/s2010194514601148.
Pełny tekst źródłaStreszczenie:
In this work, we are presenting a combination of two preliminary results for quasi-free photoproduction of η-mesons from the liquid deuterium and 3 He targets for incident photon energies from threshold up to 1.4 GeV. The experiments were performed at the Mainz MAMI electron accelerator, using the Glasgow tagged photon facility. Decay photons of the η-mesons and the recoil nucleons were detected with an almost 4π covering electromagnetic calorimeter combining the Crystal Ball and TAPS detectors. The data from both targets show a narrow structure in the excitation function of γ + n → n + η. The results from the two measurements are consistent within the expected effects from nuclear Fermi motion.
20
Su, Zhen, Joshua Cantlon, Lacey Douthit, Max Wiedorn, Sébastien Boutet, Jan Kern, Chun Hong Yoon i Daniel DePonte. "Serial crystallography using automated drop dispensing". Journal of Synchrotron Radiation 28, nr 5 (22.07.2021): 1386–92. http://dx.doi.org/10.1107/s1600577521006160.
Pełny tekst źródłaStreszczenie:
Automated, pulsed liquid-phase sample delivery has the potential to greatly improve the efficiency of both sample and photon use at pulsed X-ray facilities. In this work, an automated drop on demand (DOD) system that accelerates sample exchange for serial femtosecond crystallography (SFX) is demonstrated. Four different protein crystal slurries were tested, and this technique is further improved here with an automatic sample-cycling system whose effectiveness was verified by the indexing results. Here, high-throughput SFX screening is shown to be possible at free-electron laser facilities with very low risk of cross contamination and minimal downtime. The development of this technique will significantly reduce sample consumption and enable structure determination of proteins that are difficult to crystallize in large quantities. This work also lays the foundation for automating sample delivery.
21
Kubenova, Marzhan M., Kairat A. Kuterbekov, Malik K. Balapanov, Rais K. Ishembetov, Asset M. Kabyshev i Kenzhebatyr Z. Bekmyrza. "Some Thermoelectric Phenomena in Copper Chalcogenides Replaced by Lithium and Sodium Alkaline Metals". Nanomaterials 11, nr 9 (30.08.2021): 2238. http://dx.doi.org/10.3390/nano11092238.
Pełny tekst źródłaStreszczenie:
This review presents thermoelectric phenomena in copper chalcogenides substituted with sodium and lithium alkali metals. The results for other modern thermoelectric materials are presented for comparison. The results of the study of the crystal structure and phase transitions in the ternary systems Na-Cu-S and Li-Cu-S are presented. The main synthesis methods of nanocrystalline copper chalcogenides and its alloys are presented, as well as electrical, thermodynamic, thermal, and thermoelectric properties and practical application. The features of mixed electron–ionic conductors are discussed. In particular, in semiconductor superionic copper chalcogenides, the presence of a “liquid-like phase” inside a “solid” lattice interferes with the normal propagation of phonons; therefore, superionic copper chalcogenides have low lattice thermal conductivity, and this is a favorable factor for the formation of high thermoelectric efficiency in them.
22
Kitzerow, Heinz-S., Heinrich Matthias, Stefan L. Schweizer, Henry M. van Driel i Ralf B. Wehrspohn. "Tuning of the Optical Properties in Photonic Crystals Made of Macroporous Silicon". Advances in Optical Technologies 2008 (22.06.2008): 1–12. http://dx.doi.org/10.1155/2008/780784.
Pełny tekst źródłaStreszczenie:
It is well known that robust and reliable photonic crystal structures can be manufactured with very high precision by electrochemical etching of silicon wafers, which results in two- and three-dimensional photonic crystals made of macroporous silicon. However, tuning of the photonic properties is necessary in order to apply these promising structures in integrated optical devices. For this purpose, different effects have been studied, such as the infiltration with addressable dielectric liquids (liquid crystals), the utilization of Kerr-like nonlinearities of the silicon, or free-charge carrier injection by means of linear (one-photon) and nonlinear (two-photon) absorptions. The present article provides a review, critical discussion, and perspectives about state-of-the-art tuning capabilities.
23
Laudyn, Urszula Anna, Michał Kwaśny, Mirosław Karpierz i Gaetano Assanto. "Three-color vector nematicon". Photonics Letters of Poland 9, nr 2 (1.07.2017): 36. http://dx.doi.org/10.4302/plp.v9i2.718.
Pełny tekst źródłaStreszczenie:
Light localization via reorientation in nematic liquid crystals supports multi-component optical spatial solitons, i.e., vector nematicons. By launching three optical beams of different wavelengths and the same input polarization in a bias-free planar cell, we demonstrate a three-color vector nematicon which is self-trapped thanks to its incoherent nature. Full Text: PDF ReferencesG. I. Stegeman and M. Segev, "Optical Spatial Solitons and Their Interactions: Universality and Diversity", Science 286 (5444), 1518 (1999) CrossRef W. Królikowski and O. Bang, "Solitons in nonlocal nonlinear media: Exact solutions", Phys. Rev. E 63, 016610 (2000) CrossRef D. Suter and T. Blasberg, "Stabilization of transverse solitary waves by a nonlocal response of the nonlinear medium", Phys. Rev. A 48, 4583 (1993) CrossRef G. Assanto and M. Peccianti, "Spatial solitons in nematic liquid crystals", IEEE J. Quantum Electron. 39 (1), 13 (2003). CrossRef G. Assanto and M. Karpierz, "Nematicons: self-localised beams in nematic liquid crystals", Liq. Cryst. 36 (10), 1161 (2009) CrossRef M. Peccianti and G. Assanto, "Nematicons", Phys. Rep. 516, 147 (2012). CrossRef M. Peccianti and G. Assanto, "Incoherent spatial solitary waves in nematic liquid crystals", Opt. Lett. 26 (22), 1791 (2001) CrossRef M. Peccianti and G. Assanto, "Nematic liquid crystals: A suitable medium for self-confinement of coherent and incoherent light", Phys. Rev. E Rap. Commun. 65, 035603 (2002) CrossRef G. Assanto, M. Peccianti, C. Umeton, A. De Luca and I. C. Khoo, "Coherent and Incoherent Spatial Solitons in Bulk Nematic Liquid Crystals", Mol. Cryst. Liq. Cryst. 375, 617 (2002) CrossRef A. Alberucci, M. Peccianti, G. Assanto, A. Dyadyusha and M. Kaczmarek, "Two-Color Vector Solitons In Nonlocal Media", Phys. Rev. Lett. 97, 153903 (2006) CrossRef G. Assanto, N. F. Smyth and A. L. Worthy, "Two-color, nonlocal vector solitary waves with angular momentum in nematic liquid crystals", Phys. Rev. A 78 (1), 013832 (2008) CrossRef G. Assanto, K. Garcia-Reimbert, A. A. Minzoni, N. F. Smyth and A. Worthy, "Lagrange solution for three wavelength solitary wave clusters in nematic liquid crystals", Physica D 240, 1213 (2011) CrossRef G. Assanto, A. A. Minzoni and N. F. Smyth, "Vortex confinement and bending with nonlocal solitons", Opt. Lett. 39 (3), 509 (2014) CrossRef G. Assanto, A. A. Minzoni and N. F. Smyth, "Deflection of nematicon-vortex vector solitons in liquid crystals", Phys. Rev. A 89, 013827 (2014) CrossRef G. Assanto and N. F. Smyth, "Soliton Aided Propagation and Routing of Vortex Beams in Nonlocal Media", J. Las. Opt. Photon. 1, 105 (2014) CrossRef Y. V. Izdebskaya, G. Assanto and W. Krolikowski, "Observation of stable-vector vortex solitons", Opt. Lett. 40 (17), 4182 (2015) CrossRef Y. V. Izdebskaya, W. Krolikowski, N. F. Smyth and G. Assanto, "Vortex stabilization by means of spatial solitons in nonlocal media", J. Opt. 18 (5), 054006 (2016) CrossRef J. F. Henninot, J. Blach and M. Warenghem, "Experimental study of the nonlocality of spatial optical solitons excited in nematic liquid crystal", J. Opt. A 9, 20 (2007) CrossRef Y. V. Izdebskaya, V. G. Shvedov, A. S. Desyatnikov, W. Z. Krolikowski, M. Belic, G. Assanto and Y. S. Kivshar, "Counterpropagating nematicons in bias-free liquid crystals", Opt. Express 18 (4), 3258 (2010) CrossRef N. Karimi, A. Alberucci, M. Virkki, M. Kauranen and G. Assanto, "Phase-front curvature effects on nematicon generation", J. Opt. Soc. Am. B 5 (33), 903 (2016) CrossRef P. G. de Gennes and J. Prost, The Physics of Liquid Crystals, Oxford Science Publications (Clarendon Press, 2nd edition, 1993)I. C. Khoo, Liquid Crystals: Physical Properties and Nonlinear Optical Phenomena (Wiley, New York, 1995)A. Piccardi, M. Trotta, M. Kwasny, A. Alberucci, R. Asquini, M. Karpierz, A. d'Alessandro and G. Assanto, "Trends and trade-offs in nematicon propagation", Appl. Phys. B 104 (4), 805 (2011) CrossRef M. Kwasny, U. A. Laudyn, F. A. Sala, A. Alberucci, M. A. Karpierz and G. Assanto, "Self-guided beams in low-birefringence nematic liquid crystals", Phys. Rev. A 86 (1), 01382 (2012) CrossRef M. Peccianti, A. Fratalocchi and G. Assanto, "Transverse dynamics of nematicons", Opt. Express 12 (26), 6524 (2004) CrossRef C. Conti, M. Peccianti and G. Assanto, "Observation of Optical Spatial Solitons in a Highly Nonlocal Medium", Phys. Rev. Lett. 92 (11), 113902 (2004) CrossRef A. Alberucci, C.-P. Jisha and G. Assanto, "Breather solitons in highly nonlocal media", J. Opt. 18, 125501 (2016) CrossRef
24
Mukhin, Nikolay, Mykhailo Kutia, Alexander Aman, Ulrike Steinmann i Ralf Lucklum. "Two-Dimensional Phononic Crystal Based Sensor for Characterization of Mixtures and Heterogeneous Liquids". Sensors 22, nr 7 (6.04.2022): 2816. http://dx.doi.org/10.3390/s22072816.
Pełny tekst źródłaStreszczenie:
We show new approaches to developing acoustic liquid sensors based on phononic crystals. The proposed phononic crystal integrates fluidic elements. A solid block with periodic cylindrical holes contains a defect—a liquid-filled cylindrical cavity. We pay attention to acoustic excitation and the readout of the axisymmetric cylindrical resonator eigenmode of the liquid-filled defect in the middle of the phononic crystal structure. This mode solves the challenge of mechanical energy losses due to liquid viscosity. We also analyze the coupling effects between oscillations of liquid and solid systems and consider coupling issues between piezoelectric transducers and the liquid-filled cavity resonator. The numerical simulation of the propagation of acoustic waves through the phononic crystal sensor was carried out in COMSOL Multiphysics Software. The phononic crystal was made of stainless steel with mechanically drilled holes and was fabricated for experimental verification. We show that a tuning of the solid–liquid vibrational modes coupling is the key to an enhanced level of sensitivity to liquid properties. Besides (homogeneous) water–propanol mixtures, experimental studies were carried out on (disperse) water–fuel emulsions.
25
Zhang, Linfeng, Han Wang, Maria Carolina Muniz, Athanassios Z. Panagiotopoulos, Roberto Car i Weinan E. "A deep potential model with long-range electrostatic interactions". Journal of Chemical Physics 156, nr 12 (28.03.2022): 124107. http://dx.doi.org/10.1063/5.0083669.
Pełny tekst źródłaStreszczenie:
Machine learning models for the potential energy of multi-atomic systems, such as the deep potential (DP) model, make molecular simulations with the accuracy of quantum mechanical density functional theory possible at a cost only moderately higher than that of empirical force fields. However, the majority of these models lack explicit long-range interactions and fail to describe properties that derive from the Coulombic tail of the forces. To overcome this limitation, we extend the DP model by approximating the long-range electrostatic interaction between ions (nuclei + core electrons) and valence electrons with that of distributions of spherical Gaussian charges located at ionic and electronic sites. The latter are rigorously defined in terms of the centers of the maximally localized Wannier distributions, whose dependence on the local atomic environment is modeled accurately by a deep neural network. In the DP long-range (DPLR) model, the electrostatic energy of the Gaussian charge system is added to short-range interactions that are represented as in the standard DP model. The resulting potential energy surface is smooth and possesses analytical forces and virial. Missing effects in the standard DP scheme are recovered, improving on accuracy and predictive power. By including long-range electrostatics, DPLR correctly extrapolates to large systems the potential energy surface learned from quantum mechanical calculations on smaller systems. We illustrate the approach with three examples: the potential energy profile of the water dimer, the free energy of interaction of a water molecule with a liquid water slab, and the phonon dispersion curves of the NaCl crystal.
26
Gil-Valverde, Manuel, Manuel Cano-García, Rodrigo Delgado, Tianyi Zuo, José Manuel Otón, Xabier Quintana i Morten Andreas Geday. "Polymer selective laser curing for integrated optical switches". Photonics Letters of Poland 9, nr 1 (3.04.2017): 32. http://dx.doi.org/10.4302/plp.v9i1.710.
Pełny tekst źródłaStreszczenie:
A simple in-layer electro optical switch has been prepared by selectively curing a photocurable optical polymer with a UV laser. The core of the device is a NOA-81 multimode waveguide grown by selective laser curing. The cladding is a positive calamitic liquid crystal, which allows tunability and switching of the waveguide by external driving electric signals. The effective refractive index in the guide changes upon switching the liquid crystal. Depending on the geometry, this setup leads to an electrooptical modulator or a switch between two levels of transmitted light. Full Text: PDF ReferencesT. Ako, A. Hope, T. Nguyen, A. Mitchell, W. Bogaerts, K. Neyts, and J. Beeckman, "Electrically tuneable lateral leakage loss in liquid crystal clad shallow-etched silicon waveguides", Opt. Express 23, 2846 (2015). CrossRef K. Kruse, C. Middlebrook, "Laser-direct writing of single mode and multi-mode polymer step index waveguide structures for optical backplanes and interconnection assemblies", Photon. Nanostruct. - Fundamentals and Appl. 13, 66 (2015). CrossRef A. Günther, A.B. Petermann, M. Rezem, M. Rahlves, M. Wollweber, and B. Roth, European Conf. Lasers and Electro-Optics - European Quantum Electronics Conference, Munich, Germany (2015).C. Florian, S. Piazza, A. Diaspro, P. Serra, M. Duocastella, "Direct Laser Printing of Tailored Polymeric Microlenses", ACS Appl. Mater. Interfaces, 8(27), 17028 (2016). CrossRef F. Costache, M. Blasl, "Optical switching with isotropic liquid crystals", Opt. Photonik 6, 29 (2011). CrossRef M. Cano-Garcia, R. Delgado, T. Zuo, M.A. Geday, X. Quintana, Jose M. Otón, 16th OLC Topical Meeting on the Optics of Liquid Crystals, Sopot, Poland (2015).S. Ishihara, H. Wakemoto, K. Nakazima, Y. Matsuo, "The effect of rubbed polymer films on the liquid crystal alignment", Liq. Cryst. 4(6), 669 (1989). DirectLink
27
He, Juxing, Honglang Li, Yahui Tian, Qiaozhen Zhang, Zixiao Lu i Jianyu Lan. "Numerical Analysis of Viscous Dissipation in Microchannel Sensor Based on Phononic Crystal". Micromachines 12, nr 8 (21.08.2021): 994. http://dx.doi.org/10.3390/mi12080994.
Pełny tekst źródłaStreszczenie:
Phononic crystals with phononic band gaps varying in different parameters represent a promising structure for sensing. Equipping microchannel sensors with phononic crystals has also become a great area of interest in research. For building a microchannels system compatible with conventional micro-electro-mechanical system (MEMS) technology, SU-8 is an optimal choice, because it has been used in both fields for a long time. However, its mechanical properties are greatly affected by temperature, as this affects the phononic bands of the phononic crystal. With this in mind, the viscous dissipation in microchannels of flowing liquid is required for application. To solve the problem of viscous dissipation, this article proposes a simulation model that considers the heat transfer between fluid and microchannel and analyzes the frequency domain properties of phononic crystals. The results show that when the channel length reaches 1 mm, the frequency shift caused by viscous dissipation will significantly affect detecting accuracy. Furthermore, the temperature gradient also introduces some weak passbands into the band gap. This article proves that viscous dissipation does influence the band gap of phononic crystal chemical sensors and highlights the necessity of temperature compensation in calibration. This work may promote the application of microchannel chemical sensors in the future.
28
Xenikakis, Iakovos, Konstantinos Tsongas, Emmanouil K. Tzimtzimis, Dimitrios Tzetzis i Dimitrios Fatouros. "ADDITIVE MANUFACTURING OF HOLLOW MICRONEEDLES FOR INSULIN DELIVERY". International Journal of Modern Manufacturing Technologies 13, nr 3 (25.12.2021): 185–90. http://dx.doi.org/10.54684/ijmmt.2021.13.3.185.
Pełny tekst źródłaStreszczenie:
Microneedles (MN) are miniature devices capable of perforating painlessly stratum corneum and delivering active ingredients in the inner epidermal layers. Hollow microneedles (HMNs) are highly detailed objects due to their internal microchannels and thus, their fabrication with Additive Manufacturing (AM) is a challenging task. Vat polymerization techniques provide a sufficient accuracy for such microstructures. Differentiated from other approaches where stereolithography and 2-photon polymerization were adopted, this paper presents the 3D-printing of HMNs purposed for insulin delivery, using the more economic Liquid Crystal Display (LCD) method. First, different geometries (hexagon, square pyramid, beveled) were 3D printed with constant height and varying curing time, printing angle and layer resolution. Quality features in each case were captured with optical and scanning electron microscopy (SEM). The most promising geometry was found to be the beveled one due to the more refined tip area and the feasibility of non-clogged microchannel formation. Among printing parameters, printing angle proved to be the most influential, as it affects resin flow phenomenon during printing process. Lastly, optimized HMN geometry was the beveled configuration, where the average height was measured 900μm, 3D printing angle was set at -45°, the curing time was 10s per layer and the optimal layer height was 30μm.
29
Chen, Michelle, Matthew D. Krzyaniak, Jordan N. Nelson, Youn Jue Bae, Samantha M. Harvey, Richard D. Schaller, Ryan M. Young i Michael R. Wasielewski. "Quintet-triplet mixing determines the fate of the multiexciton state produced by singlet fission in a terrylenediimide dimer at room temperature". Proceedings of the National Academy of Sciences 116, nr 17 (4.04.2019): 8178–83. http://dx.doi.org/10.1073/pnas.1820932116.
Pełny tekst źródłaStreszczenie:
Singlet fission (SF) is a photophysical process in which one of two adjacent organic molecules absorbs a single photon, resulting in rapid formation of a correlated triplet pair (T1T1) state whose spin dynamics influence the successful generation of uncorrelated triplets (T1). Femtosecond transient visible and near-infrared absorption spectroscopy of a linear terrylene-3,4:11,12-bis(dicarboximide) dimer (TDI2), in which the two TDI molecules are directly linked at one of their imide positions, reveals ultrafast formation of the (T1T1) state. The spin dynamics of the (T1T1) state and the processes leading to uncoupled triplets (T1) were studied at room temperature for TDI2aligned in 4-cyano-4′-pentylbiphenyl (5CB), a nematic liquid crystal. Time-resolved electron paramagnetic resonance spectroscopy shows that the (T1T1) state has mixed5(T1T1) and3(T1T1) character at room temperature. This mixing is magnetic field dependent, resulting in a maximum triplet yield at ∼200 mT. The accessibility of the3(T1T1) state opens a pathway for triplet–triplet annihilation that produces a single uncorrelated T1state. The presence of the5(T1T1) state at room temperature and its relationship with the1(T1T1) and3(T1T1) states emphasize that understanding the relationship among different (T1T1) spin states is critical for ensuring high-yield T1formation from singlet fission.
30
Dohle, Rainer, Ilaria Sacco, Thomas Rittweg, Thomas Friedrich, Gerold Henning, Jörg Goßler i Peter Fischer. "LTCC-Based Highly Integrated SiPM Module with Integrated Liquid Cooling Channels for High Resolution Molecular Imaging". Journal of Microelectronics and Electronic Packaging 15, nr 2 (1.04.2018): 86–94. http://dx.doi.org/10.4071/imaps.562590.
Pełny tekst źródłaStreszczenie:
We present a very compact hybrid detection module based on an advanced liquid-cooled low temperature cofired ceramic (LTCC) substrate. The double sided hybrid combines 144 photo detectors and four specialized flip chip readout ASICs (Application specific Integrated Circuits) used for the readout of scintillation crystals with application in time-of-flight positron emission tomography (PET) combined with magnetic resonance imaging (MRI). If MRI images and PET images are combined, completely new medical diagnostic and treatment prospects are feasible because the two techniques are complementary and they will offer both anatomical and functional information. One of the biggest challenges is the development of miniaturized detector modules that are highly functional and MRI compatible. Our SiPM (Silicon Photomultiplier) module has an area of 32.8 by 32.0 mm2 and contains 12 × 12 SiPMs in a pitch of 2.5 mm2. The SiPM readout of the 144 channels is performed by four PETA6 ASICs. The LTCC substrate with a 2.1 mm thickness has been manufactured using the most advanced technologies developed at Micro Systems Engineering GmbH To guarantee the manufacturability in serial or mass production, DP951 P2 green tape has been used. For the cooling channels, special technology has been developed by MSE. The liquid cooling channels inside the LTCC substrate provide excellent cooling for the ASICs, the SiPMs, and thermal insulation between ASICs and SiPMs and allow a very compact design of the detector modules, reducing their height by 50% compared with other technical solutions. We can insert a ring of our modules in an existing MR (Magnetic Resonance) scanner. Operating the SiPMs at low temperature improves their performance, reducing the effects of dark count rate and improving image quality. There is no heatsink, heat pipe, or other cooling element attached to the back side of the ASICs. To avoid interference between the PET and MRI system, short signal length is required for minimizing pickup loops and eddy currents. The 12 SiPM arrays with 2 × 6 geometry are wire bonded only at the edges of the SiPMs to the LTCC, enabling the use of nearly the whole detector area for photon detection, which is of paramount importance for excellent image quality. At the opposite side of the substrate, four ASICs with 272 μm bump pitch are flip chip solder assembled to the LTCC substrate including underfilling, and a few SMD (Surface Mount Device) components are mounted. A scintillator crystal array on top of the SiPMs converts gamma rays (511 keV photons produced from positron-electron annihilation) into light. We assume that the LTCC substrates and all components are fully MRI compatible, which is important for the integration of PET with MRI without mutual interference. The paper elucidates the impact of the used technology on the performance of advanced PET/MRI detector modules.
31
Mukhin, Nikolay, Mykhailo Kutia, Aleksandr Oseev, Ulrike Steinmann, Stefan Palis i Ralf Lucklum. "Narrow Band Solid-Liquid Composite Arrangements: Alternative Solutions for Phononic Crystal-Based Liquid Sensors". Sensors 19, nr 17 (29.08.2019): 3743. http://dx.doi.org/10.3390/s19173743.
Pełny tekst źródłaStreszczenie:
Periodic elastic composite structures attract great attention. They offer the ability to design artificial properties to advance the control over the propagation of elastic/acoustic waves. In previous work, we drew attention to composite periodic structures comprising liquids. It was shown that the transmission spectrum of the structure, specifically a well-isolated peak, follows the material properties of liquid constituent in a distinct manner. This idea was realized in several liquid sensor concepts that launched the field of phononic crystal liquid sensors. In this work we introduce a novel concept—narrow band solid-liquid composite arrangements. We demonstrate two different concepts to design narrow band structures, and show the results of theoretical studies and results of experimental investigations that confirm the theoretical predictions. This work extends prior studies in the field of phononic crystal liquid sensors with novel concepts and results that have a high potential in a field of volumetric liquid properties evaluation.
32
Mukhin, Nikolay, i Ralf Lucklum. "Periodic Tubular Structures and Phononic Crystals towards High-Q Liquid Ultrasonic Inline Sensors for Pipes". Sensors 21, nr 17 (6.09.2021): 5982. http://dx.doi.org/10.3390/s21175982.
Pełny tekst źródłaStreszczenie:
The article focuses on a high-resolution ultrasound sensor for real-time monitoring of liquid analytes in cylindrical pipes, tubes, or capillaries. The development of such a sensor faces the challenges of acoustic energy losses, including dissipation at liquid/solid interface and acoustic wave radiation along the pipe. Furthermore, we consider acoustic resonant mode coupling and mode conversion. We show how the concept of phononic crystals can be applied to solve these problems and achieve the maximum theoretically possible Q-factor for resonant ultrasonic sensors. We propose an approach for excitation and measurement of an isolated radial resonant mode with minimal internal losses. The acoustic energy is effectively localized in a narrow probing area due to the introduction of periodically arranged sectioned rings around the tube. We present a sensor design concept, which optimizes the coupling between the tubular resonator and external piezoelectric transducers. We introduce a 2D-phononic crystal in the probing region for this purpose. The Q-factor of the proposed structures show the high prospects for phononic crystal pipe sensors.
33
Dohle, Rainer, Ilaria Sacco, Thomas Rittweg, Thomas Friedrich, Gerold Henning, Jörg Goßler i Peter Fischer. "LTCC Based Highly Integrated SiPM Module With Integrated Liquid Cooling Channels for High Resolution Molecular Imaging". International Symposium on Microelectronics 2017, nr 1 (1.10.2017): 000398–405. http://dx.doi.org/10.4071/isom-2017-wp32_006.
Pełny tekst źródłaStreszczenie:
Abstract We present a very compact hybrid detection module based on an advanced liquid-cooled LTCC substrate. The double sided hybrid combines 144 photo detectors and 4 specialized flip-chip readout ASICs used for the readout of scintillation crystals with application in time-of-flight (TOF) Positron Emission Tomography (PET) combined with Magnetic Resonance Imaging (MRI). Positron Emission Tomography is mostly known for its use in oncology applications, cardiovascular disease, and imaging of brain functions. If MRI images and PET images are combined, completely new medical diagnostic and treatment prospects are feasible since MRI delivers precise anatomical information. One of the biggest challenges is the development of miniaturized detector modules that are highly functional and MRI compatible. Our SiPM module has an area of 32.8 by 32.0 mm2 and contains 12 × 12 SiPMs in a pitch of 2.5 mm2. The SiPM readout of the 144 channels is performed by four PETA6 ASICs. The LTCC substrate with 2.1 mm thickness has been manufactured using the most advanced technologies developed at MSE. In order to guarantee the manufacturability in serial or mass production, DP951 P2 green tape has been used. For the cooling channels, special technology has been developed by MSE. The liquid cooling channels inside the LTCC substrate provide excellent cooling for the ASICs, the SiPMs, and thermal insulation between ASICs and SiPMs and allow a very compact design of the detector modules, reducing their height by 50% compared with other technical solutions. This makes both smaller scanners and larger detector rings possible, the latter being needed for heavier patients. We can insert a ring of our modules in an existing MR scanner. Operating the SiPMs at low temperature improves their performance, reducing the effects of dark count rate and improving image quality. There is no heat sink, heat pipe, or other cooling element attached to the back side of the ASICs. In order to avoid interference between the PET and MRI system, short signal length is required for minimizing pickup loops and eddy currents. The 12 SiPM arrays with 2×6 geometry are wire bonded only at the edges of the SiPMs to the LTCC, enabling the use of nearly the whole detector area for photon detection, which is of paramount importance for excellent image quality. At the opposite side of the substrate, four ASICs with 272 μm bump pitch are flip-chip solder assembled to the LTCC substrate including underfilling, and a few SMD components are mounted. A scintillator crystal array on top of the SiPMs converts gamma-rays (511 keV photons produced from positron-electron annihilation) into light. LTCC substrates and all components are fully MRI compatible, which allows integration of PET with magnetic resonance imaging without mutual interference. The performance of a PET detector is characterized by its time resolution, energy resolution, detection efficiency, and spatial resolution. Each of these factors has a huge influence on the quality of the final PET image. All of these factors are improved with our novel technical solution. With measurements on prototypes, state-of-the-art coincidence time resolution (CTR) for pairs of identical detectors in combination with high spatial resolution have been obtained. The paper elucidates the impact of the employed technology on the performance of advanced PET/MRI detector modules. Novel features of the detector modules will help to enhance the “molecular sensitivity” of PET/MRI scanners.
34
Villa-Arango, Simón, David Betancur, Róbinson Torres i Panayiotis Kyriacou. "Use of Transient Time Response as a Measure to Characterize Phononic Crystal Sensors". Sensors 18, nr 11 (25.10.2018): 3618. http://dx.doi.org/10.3390/s18113618.
Pełny tekst źródłaStreszczenie:
Phononic crystals are periodic composite structures with specific resonant features that are gaining popularity in the field as liquid sensors. The introduction of a structural defect in an otherwise periodic regular arrangement can generate a resonant mode, also called defect mode, inside the characteristic band gaps of phononic crystals. The morphology, as well as the frequency in which these defect modes appear, can give useful information on the composition and properties of an analyte. Currently, only gain and frequency measurements are performed using phononic crystal sensors. Other measurements like the transient response have been implemented in resonant sensors such as quartz microbalances showing great results and proving to be a great complimentary measure to the gain and frequency measurements. In the present paper, a study of the feasibility of using the transient response as a measure to acquire additional information about the analyte is presented. Theoretical studies using the transmission line model were realized to show the impact of variations in the concentration of an analyte, in this case, lithium carbonate solutions, in the transient time of the system. Experimental realizations were also performed showing that the proposed measurement scheme presents significant changes in the resulting data, indicating the potential use of this measure in phononic crystal sensors. This proposed measure could be implemented as a stand-alone measure or as a compliment to current sensing modalities.
35
Morelli, Donald T., Joseph P. Heremans, Charles P. Beetz, Woo Sik Yoo i Hiroyuki Matsunami. "Phonon‐electron scattering in single crystal silicon carbide". Applied Physics Letters 63, nr 23 (6.12.1993): 3143–45. http://dx.doi.org/10.1063/1.110229.
Pełny tekst źródła
36
Bi, C. Z., J. Y. Ma, J. Yan, X. Fang, B. R. Zhao, D. Z. Yao i X. G. Qiu. "Electron–phonon coupling in Nb-doped SrTiO3single crystal". Journal of Physics: Condensed Matter 18, nr 8 (10.02.2006): 2553–61. http://dx.doi.org/10.1088/0953-8984/18/8/017.
Pełny tekst źródła
37
Montoya, E., F. Agulló-Rueda, S. Manotas, J. Garcı́a Solé i L. E. Bausá. "Electron–phonon coupling in Yb3+:LiNbO3 laser crystal". Journal of Luminescence 94-95 (grudzień 2001): 701–5. http://dx.doi.org/10.1016/s0022-2313(01)00350-7.
Pełny tekst źródła
38
Raszewski, Zbigniew, Wiktor Piecek, Leszek R. Jaroszewicz, Edward Nowinowski-Kruszelnicki, Paweł Perkowski, Leonid Soms, Roman Dąbrowski i in. "High Birefringence Liquid Crystals Mixtures and their Selected Applications". Advanced Materials Research 909 (marzec 2014): 12–18. http://dx.doi.org/10.4028/www.scientific.net/amr.909.12.
Pełny tekst źródłaStreszczenie:
High-Birefringence Nematic Liquid Crystals Mixtures (HBNLCM) recently developed in the Military University of Technology (Poland) are presented in this paper. Dielectric, refractometric, viscosimetric and elastomeric characteristic were determined. The properties are discussed in terms of their applicability to electro-optical devices. Applying HBNLCM of LCM to space mission (Phobos Ground) applications for a space-borne laser rangefinder was developed, manufactured and tested under cooperation between Military University of Technology (MUT) in Poland and Vavilov State Optical Institute (Vavilov SOI) in Russia. Transmission T of Liquid Crystal Cell (LCC) at λ=1.064 μm was not smaller than 95% at the aperture diameter not less than 15 mm. Switching on and switching off times in 2.5 μm thick LCC driven by voltage 10 V were not larger than 0.7 ms. Applying HBNLCM of LCM3 to refractive index matched twisted Nematic Liquid Crystal Cell of type LCNP4 for Thomson diagnostics of dense plasma was developed, manufactured and tested under cooperation between MUT in Poland and the National Research University of Information Technologies, Mechanics and Optics in Russia. Transmission T of LCNP4 at λ=1.064 μm was not smaller than 97% at the aperture diameter not less than 30 mm. Switching on time in 2.5 μm thick LCNP4 driven by voltage 200 V was not larger than 3 μs. LCNP4 can easily tolerate 0.42 J/cm2.
39
Dominici, Sébastien, Keynaz Kamranikia, Karine Mougin i Arnaud Spangenberg. "Smart Nematic Liquid Crystal Polymers for Micromachining Advances". Micromachines 14, nr 1 (1.01.2023): 124. http://dx.doi.org/10.3390/mi14010124.
Pełny tekst źródłaStreszczenie:
The miniaturization of tools is an important step in human evolution to create faster devices as well as precise micromachines. Studies around this topic have allowed the creation of small-scale objects capable of a wide range of deformation to achieve complex tasks. Molecular arrangements have been investigated through liquid crystal polymer (LCP) to program such a movement. Smart polymers and hereby liquid crystal matrices are materials of interest for their easy structuration properties and their response to external stimuli. However, up until very recently, their employment at the microscale was mainly limited to 2D structuration. Among the numerous issues, one concerns the ability to 3D structure the material while controlling the molecular orientation during the polymerization process. This review aims to report recent efforts focused on the microstructuration of LCP, in particular those dealing with 3D microfabrication via two-photon polymerization (TPP). Indeed, the latter has revolutionized the production of 3D complex micro-objects and is nowadays recognized as the gold standard for 3D micro-printing. After a short introduction highlighting the interest in micromachines, some basic principles of liquid crystals are recalled from the molecular aspect to their implementation. Finally, the possibilities offered by TPP as well as the way to monitor the motion into the fabricated microrobots are highlighted.
40
XIA, SHANGDA. "A POSSIBLE OPTICAL PHONON DECAY OF LOW-LYING ELECTRONIC CRYSTAL-FIELD STATES OF TmPO4 CRYSTAL". International Journal of Modern Physics B 06, nr 01 (10.01.1992): 59–78. http://dx.doi.org/10.1142/s0217979292000049.
Pełny tekst źródłaStreszczenie:
We present in this paper an optical phonon [Formula: see text] decay mechanism to explain the disappearance of two electronic lines at 248 cm −1 (Γ1) and 254 cm −1 (Γ4) in experimental electronic Raman scattering spectrum of TmPO 4 crystal. The [Formula: see text] phonon model of primitive cell is described in detail. The derivation and calculation of electrical-phonon coupling crystal-field Hamiltonian [Formula: see text] and the calculation of coupling matrix elements [Formula: see text] between the initial and final electron-phonon states are outlined and demonstrated. The various channels of this decay are discussed and estimated.
41
Mazin, I. I., i S. N. Rashkeev. "EFFECT OF LOW CRYSTAL SYMMETRY ON ELECTRON-PHONON COUPLING IN PEROVSKITE SUPERCONDUCTORS". International Journal of Modern Physics B 02, nr 05 (październik 1988): 893–98. http://dx.doi.org/10.1142/s0217979288000718.
Pełny tekst źródłaStreszczenie:
The electron-phonon coupling for La 2 CuO 4-type superconductors is calculated in frameworks of rigid-muffin-tin approximation by two ways: first, in spherical approximation of Gaspari-Gyorffy and, second, taking into account the proper local symmetry. In the second case electron-phonon coupling is a few times stronger than in the first one. We conclude that low local symmetry, especially on O I sites is to a great extent responsible for the strong electron-phonon coupling in perovskites.
42
Takabatake, Toshiro, Koichiro Suekuni, Tsuneyoshi Nakayama i Eiji Kaneshita. "Phonon-glass electron-crystal thermoelectric clathrates: Experiments and theory". Reviews of Modern Physics 86, nr 2 (4.06.2014): 669–716. http://dx.doi.org/10.1103/revmodphys.86.669.
Pełny tekst źródła
43
Xu, B., Y. M. Dai, J. Han, K. Wang, R. Yang, Y. X. Yang, W. Zhang, H. Xiao i X. G. Qiu. "Electron–phonon coupling in the superconducting single crystal Rb0.8Fe1.68Se2". Physica C: Superconductivity and its Applications 503 (sierpień 2014): 25–28. http://dx.doi.org/10.1016/j.physc.2014.05.004.
Pełny tekst źródła
44
Rahman, Jamil Ur, Woo Hyun Nam, Nguyen Van Du, Gul Rahman, Altaf Ur Rahman, Weon Ho Shin, Won-Seon Seo, Myong Ho Kim i Soonil Lee. "Oxygen vacancy revived phonon-glass electron-crystal in SrTiO3". Journal of the European Ceramic Society 39, nr 2-3 (luty 2019): 358–65. http://dx.doi.org/10.1016/j.jeurceramsoc.2018.09.036.
Pełny tekst źródła
45
WEI, SHU YI, FANG ZHANG, WEI LI, ZU ZHAO i WEN DENG HUANG. "ELECTRON–PHONON INTERACTION IN WURTZITE AlxGa1-xN TERNARY CRYSTAL". International Journal of Modern Physics B 21, nr 22 (10.09.2007): 3841–50. http://dx.doi.org/10.1142/s0217979207037740.
Pełny tekst źródłaStreszczenie:
Optical vibrations of the lattice and the electron-optical-phonon interaction in wurtzite ternary nitride-based crystals was studied using the pseudo-unit-cell approach. The Fröhlich coupling constants, polaron energy shifts and the effective masses of the polaron in the system were investigated using the perturbation method. It was found that the LO and TO phonons in wurtzite Al x Ga 1-x N exhibit the one-mode behavior. The effects of the unit-cell volume varying with the composition x of ternary nitride-based crystals were also investigated.
46
Doll, G. L., G. L. Eesley, S. D. Brorson, M. S. Dresselhaus, G. Dresselhaus, A. Cassanho, H. P. Jenssen i D. R. Gabbe. "Electron‐phonon relaxation rate in single‐crystal lanthanum cuprate". Applied Physics Letters 55, nr 4 (24.07.1989): 402–4. http://dx.doi.org/10.1063/1.102425.
Pełny tekst źródła
47
KUSSOW, ADIL-GERAI. "LARGE POLARON IN AN ANHARMONIC CRYSTAL LATTICE". International Journal of Modern Physics B 23, nr 01 (10.01.2009): 19–38. http://dx.doi.org/10.1142/s0217979209049255.
Pełny tekst źródłaStreszczenie:
Extending the Frohlich polaron problem to an anharmonic lattice, the author studies a polaronic state with a large radius of the wave function. The appropriate anharmonic part of the electron–phonon interaction Hamiltonian is derived, based on the methods of quantum field theory. Then, with the help of the perturbation theory, the anharmonic correction to the electron–phonon coupling constant is straightforwardly calculated. The estimate of this correction shows that the anharmonicity can considerably increase the e–ph coupling constant if the longitudinal phonon frequency is lower than ~10 meV. Several materials, molecular crystals α-sexithiophene (α-6T), α, ω dihexylsexithiophene (H-6T), and perovskite-type oxides, in which the anharmonic polaronic effects should be pronounced, are discussed. A comparison of the results with other anharmonic models of a polaronic state is drawn.
48
Ilchuk, H. A., L. I. Nykyruy, A. I. Kashuba, I. V. Semkiv, M. V. Solovyov, B. P. Naidych, V. M. Kordan, L. R. Deva, M. S. Karkulovska i R. Y. Petrus. "Electron, phonon, optical and thermodynamic properties of CdTe crystal calculated by DFT". Physics and Chemistry of Solid State 23, nr 2 (25.05.2022): 261–69. http://dx.doi.org/10.15330/pcss.23.2.261-269.
Pełny tekst źródłaStreszczenie:
Electronic and phonon band structure, thermodynamic and optical properties are studied for the CdTe crystal. We calculated the electron and phonon dispersion at high symmetry directions, density of electron and phonon state, temperature dependence feature of Raman spectra, heat capacity, free energy, entropy, enthalpy and Debay temperature estimated with the generalized gradient approximation (GGA). A Perdew–Burke–Ernzerhof functional (PBE) was utilized. To study the optical properties was use a complex dielectric function ε(ħω). All of the calculated parameters correlate well with the known experimental data.
49
Galda, Alexey, Igor V. Yurkevich i Igor V. Lerner. "Impurity Scattering in Luttinger Liquid with Electron-Phonon Coupling". Journal of Physics: Conference Series 286 (1.03.2011): 012049. http://dx.doi.org/10.1088/1742-6596/286/1/012049.
Pełny tekst źródła
50
Brik, M. G., i N. M. Avram. "Crystal Field Analysis and Electron-phonon Coupling in Sc2O3:Cr3+". Zeitschrift für Naturforschung A 59, nr 11 (1.11.2004): 799–803. http://dx.doi.org/10.1515/zna-2004-1113.
Pełny tekst źródłaStreszczenie:
Crystal field analysis of the energy level structure of the Cr3+ ion in the Sc2O3 crystal is performed, using the exchange charge model of the crystal field theory. The crystal field parameters acting on the optical electrons of the Cr3+ ion at the sites with C2 and C3i symmetry are calculated from the crystal structure data. On the basis of the comparison between experimental absorption and emission spectra and theoretically calculated energy levels of Sc2O3:Cr3+, the conclusion is made that the spectroscopic properties of the title host are determined by the Cr3+ ion at the positions of C2 local symmetry. The Stokes shift S = 4.32 and the energy of the phonons effectively interacting with an impurity center h̅ω = 499 cm−1 are derived from the experimental spectra of absorption and emission