Статті в журналах з теми "Exciton Coupling Chirality"
Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: Exciton Coupling Chirality.
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-47 статей у журналах для дослідження на тему "Exciton Coupling Chirality".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте статті в журналах для різних дисциплін та оформлюйте правильно вашу бібліографію.
1
Dhbaibi, Kais, Ludovic Favereau, Monika Srebro-Hooper, Marion Jean, Nicolas Vanthuyne, Francesco Zinna, Bassem Jamoussi, Lorenzo Di Bari, Jochen Autschbach, and Jeanne Crassous. "Exciton coupling in diketopyrrolopyrrole–helicene derivatives leads to red and near-infrared circularly polarized luminescence." Chemical Science 9, no. 3 (2018): 735–42. http://dx.doi.org/10.1039/c7sc04312k.
2
Suzuki, Takanori, Yusuke Ishigaki, Tomohiro Iwai, Yuki Hayashi, Aiichiro Nagaki, Ryo Katoono, Kenshu Fujiwara, and Jun-ichi Yoshida. "Transmission of Point Chirality to Axial Chirality for Strong Circular Dichroism in Triarylmethylium-o,o-dimers." Synlett 29, no. 16 (June 25, 2018): 2147–54. http://dx.doi.org/10.1055/s-0037-1610190.
Анотація:
Triarylmethylium-o,o-dimers adopt a twisted geometry so that two diarylmethyliums are stacked in a slipped manner. Thus, chiral auxiliaries on the aryl groups induce a preference in the axial chirality of the central biphenyl unit. Strong circular dichroism is attained through exciton coupling, which can be used for additional spectral output in their electrochromic behavior. Diastereoselectivity based on π–π stacking exhibits unique solvent effects, thus endowing multifunctional response properties.
3
Pescitelli, Gennaro. "For a Correct Application of the CD Exciton Chirality Method: The Case of Laucysteinamide A." Marine Drugs 16, no. 10 (October 16, 2018): 388. http://dx.doi.org/10.3390/md16100388.
Анотація:
The circular dichroism (CD) exciton chirality method (ECM) is a very popular approach for assigning the absolute configuration (AC) of natural products, thanks to its immediacy and ease of application. The sign of an exciton couplet (two electronic CD bands with opposite sign and similar intensity) can be directly correlated with the molecular stereochemistry, including the AC. However, a correct application of the ECM necessitates several prerequisites: knowledge of the molecular conformation; knowledge of transition moment direction; and preeminence of the exciton coupling mechanism with respect to other sources of CD signals. In recent years, by using quantum-chemical CD calculations, we have demonstrated that some previous applications of ECM were wrong or based on incorrect assumptions. In a recent publication of this journal (Mar. Drugs, 2017, 15(4), 121), the ECM was employed to assign the AC of a marine metabolite, laucysteinamide A. This is a further case of incorrect application of the method, where none of the aforementioned prerequisites is fully met. Using this example, we will discuss the criteria required for a correct application of the ECM.
4
Nishihara, Taishi, Akira Takakura, Masafumi Shimasaki, Kazunari Matsuda, Takeshi Tanaka, Hiromichi Kataura, and Yuhei Miyauchi. "Empirical formulation of broadband complex refractive index spectra of single-chirality carbon nanotube assembly." Nanophotonics 11, no. 5 (January 12, 2022): 1011–20. http://dx.doi.org/10.1515/nanoph-2021-0728.
Анотація:
Abstract Assemblies of single-walled carbon nanotubes with a specific chiral structure are promising future optofunctional materials because of their strong light–matter coupling arising from sharp optical resonances of quasi-one-dimensional excitons. Their strong optical resonances, which lie in the infrared-to-visible wavelength region, can be selected by their chiralities, and this selectivity promises a wide range of applications including photonic and thermo-optic devices. However, the broadband complex optical spectra of single-chirality carbon nanotube assemblies are scarce in the literature, which has prevented researchers and engineers from designing devices using them. Here, we experimentally determine broadband complex refractive index spectra of single-chirality carbon nanotube assemblies. Free-standing carbon nanotube membranes and those placed on sapphire substrates were fabricated via filtration of the nanotube solution prepared by the separation method using gel chromatography. Transmission and reflection spectra were measured in the mid-infrared to visible wavelength region, and the complex refractive indices of nanotube assemblies were determined as a function of photon energy. The real and imaginary parts of the refractive indices of the nanotube membrane with a bulk density of 1 g cm−3 at the first subband exciton resonance were determined to be approximately 2.7–3.6 and 1.3i–2.4i, respectively. We propose an empirical formula that phenomenologically describes the complex refractive index spectra of various single-chirality nanotube membranes, which can facilitate the design of photonic devices using carbon nanotubes as the material.
5
Cataldo, Franco. "On the Optical Activity of Poly(l-lactic acid) (PLLA) Oligomers and Polymer: Detection of Multiple Cotton Effect on Thin PLLA Solid Film Loaded with Two Dyes." International Journal of Molecular Sciences 22, no. 1 (December 22, 2020): 8. http://dx.doi.org/10.3390/ijms22010008.
Анотація:
Optical rotatory dispersion (ORD) is a beautiful analytical technique for the study of chiral molecules and polymers. In this study, ORD was applied successfully to follow the degree of polycondensation of l-(+)-lactic acid toward the formation of poly(lactic acid) oligomers (PLAO) and high molecular weight poly(l-lactic acid) (PLLA) in a simple esterification reaction equipment. PLLA is a biodegradable polymer obtainable from renewable raw materials. The racemization of the intrinsically isotactic PLLA through thermal treatment can be easily followed through the use of ORD spectroscopy. Organic or molecular electronics is a hot topic dealing with the combination of π-conjugated organic compounds and polymers with specific properties (e.g., chirality) which can be exploited to construct optoelectronic devices, such as organic light-emitting diodes (OLEDs), organic photovoltaic (OPV) high efficiency cells, switchable chirality devices, organic field-effect transistors (OFETs), and so on. ORD spectroscopy was applied to study either the gigantic optical rotation of PLLA films, as well as to detect successfully the excitonic coupling, occurring in thin solid PLLA green film loaded with a combination of two dyes: SY96 (a pyrazolone dye) and PB16 (the metal-free phthalocyanine pigment). The latter compound PLLA loaded with SY96 and PB16 shows a really gigantic optical activity in addition to typical ORD signal due to exciton coupling and may be considered as a simple and easily accessible model composite of a chiral polymer matrix combined with π-conjugated dyes for molecular electronics studies.
6
Norman, Patrick, та Mathieu Linares. "On the Interplay Between Chirality and Exciton Coupling: A DFT Calculation of the Circular Dichroism inπ-Stacked Ethylene". Chirality 26, № 9 (19 травня 2014): 483–89. http://dx.doi.org/10.1002/chir.22331.
7
A Kadir, Muhamad Faid, Agustono Wibowo, Fatimah Salim, El Hassane Anouar, Khalijah Awang, Moses Kiprotich Langat, and Rohaya Ahmad. "Conformational Analysis of Diterpene Lactone Andrographolide towards Reestablishment of Its Absolute Configuration via Theoretical and Experimental ECD and VCD Methods." Indonesian Journal of Chemistry 21, no. 1 (December 4, 2020): 148. http://dx.doi.org/10.22146/ijc.55206.
Анотація:
Andrographolide, the major constituent from the terrestrial plant Andrographis paniculata is a much-studied bioactive ent-labdane diterpene lactone and has become an important medicinal intermediate. Its structure as determined by X-ray crystallography has been applied in molecular docking studies to explain biological activities. Nevertheless, recently there has been a number of conflicting reports concerning the stereochemistry at the C-14 and C-10 positions affecting the absolute configuration (AC) of the compound. Since a lack of information on the molecular flexibility of the molecule can lead to misleading conclusions on biological activity, a conformational analysis of the molecule in the solution state was necessary. The conformational analysis was performed by the Spartan14 package using the Merck Molecular Force Field (MMFF). The exciton chirality method in electronic circular dichroism spectroscopy (ECM-ECD) and vibrational circular dichroism (VCD) techniques were then jointly employed to re-establish the AC of andrographolide. Theoretical calculations were performed using TD-DFT methods by using the hybrid functionals B3LYP and CAM-B3LYP combined with 6-31G(d,p) basis set. Long-range exciton coupling of 2-naphthoyl chromophores at C-14 and C-19 led to the establishment of the AC to be 3R, 4R, 5S, 9R, 10R and 14S. Comparison between the theoretical VCD data of 14-S and 14-R stereoisomer confirmed a configuration of S at C-14 position instead of R.
8
Occhiuto, Ilaria Giuseppina, Maria Angela Castriciano, Mariachiara Trapani, Roberto Zagami, Andrea Romeo, Robert F. Pasternack, and Luigi Monsù Scolaro. "Controlling J-Aggregates Formation and Chirality Induction through Demetallation of a Zinc(II) Water Soluble Porphyrin." International Journal of Molecular Sciences 21, no. 11 (June 3, 2020): 4001. http://dx.doi.org/10.3390/ijms21114001.
Анотація:
Under acidic conditions and at high ionic strength, the zinc cation is removed from its metal complex with 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS4) thus leading to the diacid free porphyrin, that subsequently self-organize into J-aggregates. The kinetics of the demetallation step and the successive supramolecular assembly formation have been investigated as a function of pH and ionic strength (controlled by adding ZnSO4). The demetallation kinetics obey to a rate law that is first order in [ZnTPPS4] and second order in [H+], according to literature, with k2 = 5.5 ± 0.4 M−2 s−1 at 298 K (IS = 0.6 M, ZnSO4). The aggregation process has been modeled according to an autocatalytic growth, where after the formation of a starting seed containing m porphyrin units, the rate evolves as a power of time. A complete analysis of the extinction time traces at various wavelengths allows extraction of the relevant kinetic parameters, showing that a trimer or tetramer should be involved in the rate-determining step of the aggregation. The extinction spectra of the J-aggregates evidence quite broad bands, suggesting an electronic coupling mechanism different to the usual Frenkel exciton coupling. Resonance light scattering intensity in the aggregated samples increases with increasing both [H+] and [ZnSO4]. Symmetry breaking occurs in these samples and the J-aggregates show circular dichroism spectra with unusual bands. The asymmetry g-factor decreases in its absolute value with increasing the catalytic rate kc, nulling and eventually switching the Cotton effect from negative to positive. Some inferences on the role exerted by zinc cations on the kinetics and structural features of these nanostructures have been discussed.
9
Kessinger, Roland, Carlo Thilgen, Tiziana Mordasini, and Francois Diederich. "ChemInform Abstract: Optically Active Macrocyclic cis-3 Bis-Adducts of C60: Regio- and Stereoselective Synthesis, Exciton Chirality Coupling, and Determination of the Absolute Configuration, and First Observation of Exciton Coupling Between Fullerene Chro." ChemInform 32, no. 10 (March 6, 2001): no. http://dx.doi.org/10.1002/chin.200110104.
10
Kessinger, Roland, Carlo Thilgen, Tiziana Mordasini, and François Diederich. "Optically Active Macrocycliccis-3 Bis-Adducts of C60: Regio- and Stereoselective Synthesis, Exciton Chirality Coupling, and Determination of the Absolute Configuration, and First Observation of Exciton Coupling between Fullerene Chromophores in a Chiral Environment." Helvetica Chimica Acta 83, no. 12 (December 20, 2000): 3069–96. http://dx.doi.org/10.1002/1522-2675(20001220)83:12<3069::aid-hlca3069>3.0.co;2-w.
11
Naito, Junpei, Yoko Yamamoto, Megumi Akagi, Satoshi Sekiguchi, Masataka Watanabe, and Nobuyuki Harada. "Unambiguous Determination of the Absolute Configurations of Acetylene Alcohols by Combination of the Sonogashira Reaction and the CD Exciton Chirality Method ? Exciton Coupling between Phenylacetylene and Benzoate Chromophores." Monatshefte f�r Chemie - Chemical Monthly 136, no. 3 (March 2005): 411–45. http://dx.doi.org/10.1007/s00706-005-0281-3.
12
Otsuka, Keigo, Nan Fang, Daiki Yamashita, Takashi Taniguchi, Kenji Watanabe, and Yuichiro K. Kato. "(Invited) Deterministic Transfer of Optical-Quality Carbon Nanotubes for Atomically Defined Technology." ECS Meeting Abstracts MA2022-01, no. 10 (July 7, 2022): 770. http://dx.doi.org/10.1149/ma2022-0110770mtgabs.
Анотація:
When continued device scaling reaches the ultimate limit imposed by atoms, technology based on atomically precise structures is expected to emerge. Device fabrication will then require building blocks with identified atomic arrangements and assembly of the components without contamination. Here we report on a versatile dry transfer technique for deterministic placement of optical-quality carbon nanotubes [1]. Single-crystalline anthracene is used as a medium which readily sublimes by mild heating, leaving behind clean nanotubes and thus enabling bright photoluminescence. We are able to position nanotubes of a desired chirality with a sub-micron accuracy under in-situ optical monitoring, thereby demonstrating deterministic coupling of a nanotube to a photonic crystal nanobeam cavity. A cross junction structure is also designed and constructed by repeating the nanotube transfer, where intertube exciton transfer is observed. Our results represent an important step towards development of devices consisting of atomically precise components and interfaces. Parts of this study are supported by JSPS (KAKENHI JP20H02558, JP19J00894, JP20K15137), MIC (SCOPE 191503001), and MEXT (Nanotechnology Platform JPMXP09F19UT0075). Growth of hexagonal boron nitride crystals is supported by the Element Strategy Initiative conducted by the MEXT (JPMXP0112101001), JSPS (KAKENHI JP20H00354), and JST (CREST JPMJCR15F3). K.O. and D.Y. are supported by JSPS (Research Fellowship for Young Scientists). N.F. is supported by RIKEN Special Postdoctoral Researcher Program. We thank T. Inoue, S. Maruyama, and K. Nagashio for help in the material preparation, as well as the Advanced Manufacturing Support Team at RIKEN for technical assistance. [1] K. Otsuka, N. Fang, D. Yamashita, T. Taniguchi, K. Watanabe, Y. K. Kato, Nat. Commun.12, 3138 (2021).
13
Liang, Xiongyu, Kun Liang, Xuyan Deng, Chengmao He, Peng Zhou, Junqiang Li, Jianyu Qin, Lei Jin, and Li Yu. "The Mechanism of Manipulating Chirality and Chiral Sensing Based on Chiral Plexcitons in a Strong-Coupling Regime." Nanomaterials 14, no. 8 (April 18, 2024): 705. http://dx.doi.org/10.3390/nano14080705.
Анотація:
Manipulating plasmonic chirality has shown promising applications in nanophotonics, stereochemistry, chirality sensing, and biomedicine. However, to reconfigure plasmonic chirality, the strategy of constructing chiral plasmonic systems with a tunable morphology is cumbersome and complicated to apply for integrated devices. Here, we present a simple and effective method that can also manipulate chirality and control chiral light–matter interactions only via strong coupling between chiral plasmonic nanoparticles and excitons. This paper presents a chiral plexcitonic system consisting of L-shaped nanorod dimers and achiral molecule excitons. The circular dichroism (CD) spectra in our strong-coupling system can be calculated by finite element method simulations. We found that the formation of the chiral plexcitons can significantly modulate the CD spectra, including the appearance of new hybridized peaks, double Rabi splitting, and bisignate anti-crossing behaviors. This phenomenon can be explained by our extended coupled-mode theory. Moreover, we explored the applications of this method in enantiomer ratio sensing by using the properties of the CD spectra. We found a strong linear dependence of the CD spectra on the enantiomer ratio. Our work provides a facile and efficient method to modulate the chirality of nanosystems, deepens our understanding of chiral plexcitons in nanosystems, and facilitates the development of chiral devices and chiral sensing.
14
Kono, Junichiro. "(Invited, Digital Presentation) Macroscopically Aligned Carbon Nanotubes for Photonics, Electronics, and Thermoelectrics." ECS Meeting Abstracts MA2022-01, no. 10 (July 7, 2022): 775. http://dx.doi.org/10.1149/ma2022-0110775mtgabs.
Анотація:
The remarkable flexibility, stable chemical structure, and extraordinary thermal, electrical, and optical properties of carbon nanotubes (CNTs) are promising for a variety of applications in flexible and/or high-temperature electronics, optoelectronics, and thermoelectrics, including wearables, refractory photonics, and waste heat harvesting [1]. However, the long-standing goal in the preparation of CNT ensembles is how to maintain the extraordinary properties of individual CNTs on a macroscopic scale. The polydispersity and randomness remain two main challenges. Here, we will discuss different methods for creating macroscopically aligned CNTs, including spontaneous formation of wafer-scale aligned CNT films via controlled vacuum filtration [2-4] and production of ultrahigh-conductivity CNT fibers and films through solution spinning and coating [5,6]. We will then describe the optical [2,7-11], dc and ac electrical [2,12-17], thermal [18], and thermoelectric [19-21] properties of these materials. These results are promising for device applications in various fields such as flexible CNT broadband detectors [22-26], spectrally selective thermal emitters [11], and thermoelectric devices [20,21]. W. Gao et al., “Macroscopically Aligned Carbon Nanotubes for Flexible and High-Temperature Electronics, Optoelectronics, and Thermoelectrics,” Journal of Physics D: Applied Physics 53, 063001 (2020). X. He et al., “Wafer-Scale Monodomain Films of Spontaneously Aligned Single-Walled Carbon Nanotubes,” Nature Nanotechnology 11, 633 (2016). W. Gao and J. Kono, “Science and Applications of Wafer-Scale Crystalline Carbon Nanotube Films Prepared through Controlled Vacuum Filtration,” Royal Society Open Science 6, 181605 (2019). N. Komatsu et al., “Groove-Assisted Global Spontaneous Alignment of Carbon Nanotubes in Vacuum Filtration,” Nano Letters 20, 2332 (2020). N. Behabtu et al., “Strong, Light, Multifunctional Fibers of Carbon Nanotubes with Ultrahigh Conductivity,” Science 339, 182 (2013). L. W. Taylor et al., “Improved Properties, Increased Production, and the Path to Broad Adoption of Carbon Nanotube Fibers,” Carbon 171, 689 (2021). K. Yanagi et al., “Intersubband Plasmons in the Quantum Limit in Gated and Aligned Carbon Nanotubes,” Nature Communications 9, 1121 (2018). W. Gao et al., “Continuous Transition between Weak and Ultrastrong Coupling through Exceptional Points in Carbon Nanotube Microcavity Exciton–Polaritons,” Nature Photonics 12, 362 (2018). M. E. Green et al., “Bright and Ultrafast Photoelectron Emission from Aligned Single-Wall Carbon Nanotubes through Multiphoton Exciton Resonance,” Nano Letters 19, 158 (2019). F. Katsutani et al., “Direct Observation of Cross-Polarized Excitons in Aligned Single-Chirality Single-Wall Carbon Nanotubes,” Physical Review B 99, 035426 (2019). W. Gao et al., “Macroscopically Aligned Carbon Nanotubes as a Refractory Platform for Hyperbolic Thermal Emitters,” ACS Photonics 6, 1602 (2019). X. Wang et al., “High-Ampacity Power Cables of Tightly-Packed and Aligned Carbon Nanotubes,” Advanced Functional Materials 24, 3241 (2014). A. Zubair et al., “Carbon Nanotube Fiber Terahertz Polarizer,” Applied Physics Letters 108, 141107 (2016). D. Tristant et al., “Enlightening the Ultrahigh Electrical Conductivities of Doped Double-Wall Carbon Nanotube Fibers by Raman Spectroscopy and First-Principles Calculations,” Nanoscale 18, 19668 (2016). N. Komatsu et al., “Modulation-Doped Multiple Quantum Wells of Aligned Single-Wall Carbon Nanotubes,” Advanced Functional Materials 27, 1606022 (2017). F. R. G. Bagsican et al., “Terahertz Excitonics in Carbon Nanotubes: Exciton Autoionization and Multiplication,” Nano Letters 20, 3098 (2020). A. Baydin et al., “Giant Terahertz Polarization Rotation in Ultrathin Films of Aligned Carbon Nanotubes,” Optica 8, 760 (2021). S. Yamaguchi et al., “One-Directional Thermal Transport in Densely Aligned Single-Wall Carbon Nanotube Films,” Applied Physics Letters 115, 223104 (2019). K. Fukuhara et al., “Isotropic Seebeck Coefficient of Aligned Single-Wall Carbon Nanotube Films,” Applied Physics Letters 113, 243105 (2018). Y. Ichinose et al., “Solving the Thermoelectric Trade-Off Problem with Metallic Carbon Nanotubes,” Nano Letters 19, 7370 (2019). N. Komatsu et al., “Macroscopic Weavable Fibers of Carbon Nanotubes with Giant Thermoelectric Power Factor,” Nature Communications 12, 4931 (2021). S. Nanot et al., “Broadband, Polarization-Sensitive Photodetector Based on Optically-Thick Films of Macroscopically Long, Dense, and Aligned Carbon Nanotubes,” Scientific Reports 3, 1335 (2013). X. He et al., “Photothermoelectric p-n Junction Photodetector with Intrinsic Broadband Polarimetry Based on Macroscopic Carbon Nanotube Films,” ACS Nano 7, 7271 (2013). X. He et al., “Carbon Nanotube Terahertz Detector,” Nano Letters 14, 3953 (2014). X. He, F. Léonard, and J. Kono, “Uncooled Carbon Nanotube Photodetectors,” Advanced Optical Materials 3, 989 (2015). A. Zubair et al., “Carbon Nanotube Woven Textile Photodetector,” Physical Review Materials 2, 015201 (2018).
15
Cheng, Haowei, Kun Liang, Xuyan Deng, Lei Jin, Jingcheng Shangguan, Jiasen Zhang, Jiaqi Guo, and Li Yu. "Optical Chirality of Gold Chiral Helicoid Nanoparticles in the Strong Coupling Region." Photonics 10, no. 3 (February 27, 2023): 251. http://dx.doi.org/10.3390/photonics10030251.
Анотація:
The far- and near-field chirality properties are usually characterized by circular dichroism (CD) and optical chirality (OC), respectively. As a light–matter interaction for the hybrid states consisting of plasmons and excitons, the strong coupling interactions can affect the original chiral electromagnetic modes. However, there are few works on this influence process, which prevents an in-depth understanding of chirality. Here, we theoretically investigate both the far-field and near-field characteristics of the chiral plasmonic gold helicoid nanoparticle (GHNP) to explore the chirality mechanism further. We found that the electromagnetic field distribution of GHNP consists of one dark mode and two bright modes. The dark mode is observed more clearly in CD than in extinction spectra. Two bright modes can strongly couple with excitons respectively, which is confirmed by the anticrossing behavior and mode splitting exhibited in the extinction and CD spectra. We also analyzed the near-field OC distribution of the GHNP hybrid system and obtained the chiral responses as well as the spectral correspondence between OC and CD. Furthermore, although the strong coupling interaction changes the energy levels, resulting in mode splitting, the chiral hotspot distributions of both the upper polariton branch and lower polariton branch are consistent with the original bright mode in OC maps. Our findings provide guidance for the design of structures with strong chiral responses and enhance the comprehension of chiral strong coupling systems.
16
Petronijevic, Emilija, Ramin Ghahri, and Concita Sibilia. "Plasmonic Elliptical Nanohole Arrays for Chiral Absorption and Emission in the Near-Infrared and Visible Range." Applied Sciences 11, no. 13 (June 28, 2021): 6012. http://dx.doi.org/10.3390/app11136012.
Анотація:
Chiral plasmonic nanostructures with tunable handedness-dependent absorption in the visible and infrared offer chiro-optical control at the nanoscale. Moreover, coupling them with emitting layers could lead to chiral nanosources, important for nanophotonic circuits. Here, we propose plasmonic elliptical nanohole arrays (ENHA) for circularly dependent near-infrared and visible emission. We first investigate broadband chiral behavior in an Au-ENHA embedded in glass by exciting it with plane waves. We then study the coupling of ENHA with a thin emitting layer embedded in glass; we focus on the emission wavelengths which provided high chirality in plane-wave simulations. Our novel simulation set-up monitors the chirality of the far-field emission by properly averaging a large set of homogeneously distributed, randomly oriented quantum sources. The intrinsic chirality of ENHA influences the circular polarization degree of the emitting layer. Finally, we study the emission dependence on the field distribution at the excitation wavelength. We demonstrate the chiral absorption and emission properties for Au-ENHA emitting in the near-infrared range, and for Ag-ENHA which is excited in green range and emits in the Lumogen Red range. The simple geometry of ENHA can be fabricated with low-cost nanosphere lithography and be covered with emission gel. We thus believe that this design can be of great importance for tunable chiral nanosources.
17
Tretiak, Sergei. "(Invited) On-the-Fly Non-Adiabatic Dynamics Simulations of Single-Walled Carbon Nanotubes with Covalent Defects." ECS Meeting Abstracts MA2023-01, no. 10 (August 28, 2023): 1183. http://dx.doi.org/10.1149/ma2023-01101183mtgabs.
Анотація:
Single-walled carbon nanotubes (SWCNTs) with covalent surface defects have been explored recently due to their promise for use in single-photon telecommunication emission and in spintronic applications. The dynamical evolution of excitons (the primary electronic excitations) in these systems has only been loosely explored using atomistic modeling due to the size-limitations of these large systems. We present computational modeling of non-radiative relaxation on a variety of SWCNT chiralities with single-defect functionalization schemes. Our modeling uses a trajectory surface hopping algorithm accounting for excitonic effects with a configuration interaction approach. We find a strong chirality and defect-composition dependence on the population relaxation (50 – 500 fs) between the nanotube band-gap excitation and the defect-associated, single-photon-emitting state, giving insight into the dynamic trapping nature of these localized excitonic states. Engineering fast population decay into the quasi-two-level sub-system with weak coupling to higher-energy states increases the effectiveness and controllability of these quantum light emitters.
18
Zhang, Qiang, Zhirong Liu, and Ziqiang Cheng. "Chiral Mechanical Effect of the Tightly Focused Chiral Vector Vortex Fields Interacting with Particles." Nanomaterials 13, no. 15 (August 4, 2023): 2251. http://dx.doi.org/10.3390/nano13152251.
Анотація:
The coupling of the spin-orbit angular momentum of photons in a focused spatial region can enhance the localized optical field’s chirality. In this paper, a scheme for producing a superchiral optical field in a 4π microscopic system is presented by tightly focusing two counter-propagating spiral wavefronts. We calculate the optical forces and torques exerted on a chiral dipole by the chiral light field and reveal the chiral forces by combining the light field and dipoles. Results indicate that, in addition to the general optical force, particles’ motion would be affected by a chiral force that is directly related to the particle chirality. This chiral mechanical effect experienced by the electromagnetic dipoles excited on a chiral particle could be characterized by the behaviors of chirality density and flux, which are, respectively, associated with the reactive and dissipative components of the chiral forces. This work facilitates the advancement of optical separation and manipulation techniques for chiral particles.
19
Schanne-Klein, M. C., T. Boulesteix, F. Hache, M. Alexandre, G. Lemercier, and C. Andraud. "Strong chiroptical effects in surface second harmonic generation obtained for molecules exhibiting excitonic coupling chirality." Chemical Physics Letters 362, no. 1-2 (August 2002): 103–8. http://dx.doi.org/10.1016/s0009-2614(02)01030-8.
20
Maruyama, Shigeo. "(Invited) Optical Properties and Device Application of One-Dimensional Vdw Heterostructures Based on Single-Walled Carbon Nanotubes." ECS Meeting Abstracts MA2023-01, no. 10 (August 28, 2023): 1205. http://dx.doi.org/10.1149/ma2023-01101205mtgabs.
Анотація:
A typical one-dimensional (1D) van der Waals (vdW) heterostructure consists of SWCNT, boron nitride nanotube (BNNT), and molybdenum disulfide nanotube (MoS2NT), grown coaxially by successive chemical vapor deposition (CVD) steps [1, 2]. The coaxially nested structure based on SWCNTs, which has diverse electronic properties (metallic or semiconducting), can expand the board application possibilities of 1D vdW heterostructures [3]. By comparing the optical properties of films of BNNT@MoS2NT and SWCNT@BNNT@MoS2NT, we found strong photoluminescence (PL) from monolayer MoS2NT and quenching of PL by coupling to SWCNT through thin BNNT [4]. The inter-tube excitons are demonstrated by ultrafast optical spectroscopy [5]. The inter-tube excitons, the counterpart of inter-layer excitons for 2D heterostructures, suggest a possibility of efficient photovoltaic applications of the 1D heterostructure [6]. In addition to MoS2 nanotubes, we will discuss the growth control of WS2 and NbS2 nanotubes. A general strategy we can tune the CVD condition from 2D flake to 1D tube is proposed. The junctions of MoS2 and WS2 nanotube are also realized as the outermost layer. More specific optical properties are studied for semiconductor SWCNTs and chirality-sorted SWCNTs [7,8]. Semiconductor SWCNT or chirality-sorted SWCNT wrapped with BNNT can be regarded as the ideal building blocks of field-effect transistors (FET) [9]. We have demonstrated the radial semiconductor–insulator–semiconductor (S-I-S) tunneling heterojunction diode by using a micrometer long 1D vdW heterostructure SWCNT@BNNT@MoS2NT [10]. We will discuss a more recent array of 1D heterostructure FET devices. Part of this work was supported by JSPS KAKENHI Grant Number JP20H00220, and by JST, CREST Grant Number JPMJCR20B5, Japan. References: [1] R. Xiang et al., Science 367, 537 (2020). [2] Y. Zheng, et al, P. Natl. Acad. Sci., 118, e2107295118 (2021). [3] S. Cambré, et al., Small, 17, 2102585 (2021). [4] M. Liu et al., ACS Nano 15, 8418 (2021). [5] M. G. Burdanova et al., Adv. Funct. Mater. 32, 2104969 (2022). [6] R. Xiang, Y. Li, S. Maruyama, National Science Open, 1, 20220016 (2022). [7] R. Zhang et al., Carbon 199, 407 (2022). [8] C. Zhang et al., ACS Nano 16, 18630 (2022). [9] R. Xiang, S. Maruyama, Small Sci., 1, 2000039 (2021). [10] Y. Feng, et al., ACS Nano, 15, 5600 (2021).
21
Guo, Si-Jia, Yu-Zeng Li, Tian-Zi Li, Xi-Ying Fan, and Chun-Yin Qiu. "Topological properties of non-isotropic two-dimensional SSH model." Acta Physica Sinica 71, no. 7 (2022): 070201. http://dx.doi.org/10.7498/aps.71.20211967.
Анотація:
<sec>The one-dimensional (1D) Su-Schrieffer-Heeger (SSH) chain is a model that has been widely studied in the field of topological physics. The two-dimensional (2D) SSH model is a 2D extension of the 1D SSH chain and has many unique physical properties. It is a higher-order topological insulator (HOTI), in which corner states with bound states in the continuum (BIC) properties will arise between the second energy band and the third energy band. There are two different topological phases in the isotropic 2D SSH model, and a topological phase transition will happen when the intracell coupling strength is equal to the intercell coupling strength.</sec><sec>In this paper, we first break the isotropy of the isotropic 2D SSH model, defining the ratio of the <i>x</i>-directional coupling strength to the <i>y</i>-directional coupling strength as <i>α</i> and the ratio of the intercell coupling strength to the intracell coupling strength as <i>β</i>, which represent the strength of the topological property and anisotropy respectively. We use <i>α</i> and <i>β</i> to calibrate all possible models, classify them as three different types of phases, and draw their phase diagrams.Then we argue when the energy gap between the second energy band and the third energy band emerges over the entire Brillouin zone.</sec><sec>Meanwhile, we use a method to calculate the spatial distribution of polarization when the model is half-filled, and it is shown that there is 1/2 polarization localized at the edges in the direction with larger intracell coupling, but no edge polarization in the other direction. The edge polarization excites the edge dipole moment, giving rise to a topological edge state in the energy gap. At the same time, when the model has an entire open boundary, the dipole moment directs the charge to accumulate on the corners, which can be observed from the local charge density distribution. This type of fractional charge is a filling anomaly and formed spontaneously by the lattice to maintain electrical neutrality and rotational symmetry simultaneously. This fractional charge induces the aforementioned corner state. And by its nature of filling anomaly, this corner state is better localized and robust. It will not couple with the bulk state as long as the rotational symmetry or chirality of the model is not broken.</sec><sec>Finally, we construct an acoustic resonant cavity model: a rectangular shaped resonant cavity is used to simulate individual lattice points and the coupling strength between the lattice points is controlled by varying the diameter of the conduit between the resonant cavities. According to the Comsol calculation results, we can see that the topological properties of the anisotropic two-dimensional SSH model are well simulated by this model.</sec>
22
Han, Mei-rong, Shao-dong Li, Ling Ma, Bang Yao, Si-Si Feng, and Miao-li Zhu. "Luminescent and magnetic bifunctional coordination complex based on a chiral tartaric acid derivative and europium." Acta Crystallographica Section C Structural Chemistry 75, no. 9 (August 6, 2019): 1220–27. http://dx.doi.org/10.1107/s205322961901060x.
Анотація:
A new mononuclear europium complex incorporating the (+)-di-p-toluoyl-D-tartaric acid (D-H2DTTA) ligand, namely, catena-poly[tris{μ2-3-carboxy-2,3-bis[(4-methylphenyl)carbonyloxy]propanoato}tris(methanol)europium(III)], [Eu(C20H17O8)3(CH3OH)3] n , (I), has been synthesized and characterized by IR spectroscopy, elemental analysis, powder X-ray diffraction and single-crystal X-ray diffraction analysis. The structure analysis indicates that complex (I) crystallizes in the trigonal space group R3 and exhibits an infinite one-dimensional chain structure, in which the Eu3+ ion is surrounded by six O atoms from six D-HDTTA− ligands and three O atoms from three coordinated methanol molecules, thus forming a tricapped trigonal prism geometry. The D-H2DTTA ligand is partially deprotonated and adopts a μ1,6-coordination mode via two carboxylate groups to link adjacent Eu3+ ions, affording an infinite one-dimensional propeller-shaped coordination polymer chain along the c axis, with an Eu...Eu distance of 7.622 (1) Å. Moreover, C—H...π interactions lead to the formation of helical chains running along the c axis and the whole structure displays a snowflake pattern in the ab plane. The circular dichroism spectrum confirms the chirality of complex (I). The solid-state photoluminescence properties were also investigated at room temperature and (I) exhibits characteristic red emission bands derived from the Eu3+ ion (CIE 0.63, 0.32), with a reasonably long lifetime of 0.394 ms, indicating effective energy transfer from the ligand to the metal centre. In addition, a magnetic investigation reveals single-ion magnetic behaviour. The spin-orbit coupling parameter (λ) between the ground and excited states is fitted to be 360 (2) cm−1 through Zeeman perturbation. Therefore, complex (I) may be regarded as a chiral optical-magneto bifunctional material.
23
Dhbaibi, Kais, Paola Matozzo, Laura Abella, Marion Jean, Nicolas Vanthuyne, Jochen Autschbach, Ludovic Favereau, and Jeanne Crassous. "Exciton coupling chirality in helicene-porphyrin conjugates." Chemical Communications, 2021. http://dx.doi.org/10.1039/d1cc03314j.
Анотація:
prepared. They show strong changes in their circular dichroic response as compared to classical helicene derivatives, with highly intense bisignate Exciton Coupling (EC) signal and Δε values up to 680...
24
Nakano, Tamaki, Adriana Pietropaolo, and Masahiro Kamata. "Chirality analysis of helical polymers." Chemistry Teacher International, November 26, 2020. http://dx.doi.org/10.1515/cti-2020-0009.
Анотація:
AbstractOptically active macromolecules, having a preferred- or single-handed helical conformation, play important roles in polymeric materials and in life. This article presents how helical polymers can be assessed from a view of chirality. These assessments, based on optical rotation (OR) and circular dichroism (CD) spectral measurements with associated information, include theoretical spectral calculations as well as chromatographic resolution. Specific applied examples are discussed for poly(9,9-dioctylfluorene-2,7-diyl) and derivatives, stereoregular polyolefins bearing centers of chirality in the side chain, isotactic poly(triphenylmethyl methacrylate), and π-stacked poly(dibenzofulvene). For more convincing establishment of a helix, it is important to correlate chiroptical properties with related information such as molar-mass effects, temperature effects, and chemical transformation effects on the properties. Helices of the polyolefins and poly(TrMA) were confirmed considering these aspects. In addition, comparison of chiroptical properties between the polymer in question and a monomeric unit model compound generally helps to confirm a helix. There are no general, reliable methods to quantify helical sense excess. On the other hand, absolute helical sense can be determined by comparing experimental and theoretical CD spectra as well as considering exciton coupling effects in CD spectra. The former method can be more generally applied for a wide range of polymers as far as a good model for calculations is designed, while the latter can be more conveniently and empirically applied for a certain class of polymer structures that are suited to exhibit exciton coupling without using computers.
25
Chen, Yichuan, and Mengtao Sun. "Plexcitonics: plasmon–exciton coupling for enhancing spectroscopy, optical chirality, and nonlinearity." Nanoscale, 2023. http://dx.doi.org/10.1039/d3nr01388j.
26
Goupalov, S. V., B. C. Satishkumar, and S. K. Doorn. "Excitation and chirality dependence of the exciton-phonon coupling in carbon nanotubes." Physical Review B 73, no. 11 (March 1, 2006). http://dx.doi.org/10.1103/physrevb.73.115401.
27
Lujan, David, Jeongheon Choe, Swati Chaudhary, Gaihua Ye, Cynthia Nnokwe, Martin Rodriguez-Vega, Jiaming He, et al. "Spin–orbit exciton–induced phonon chirality in a quantum magnet." Proceedings of the National Academy of Sciences 121, no. 11 (March 8, 2024). http://dx.doi.org/10.1073/pnas.2304360121.
Анотація:
The interplay of charge, spin, lattice, and orbital degrees of freedom in correlated materials often leads to rich and exotic properties. Recent studies have brought new perspectives to bosonic collective excitations in correlated materials. For example, inelastic neutron scattering experiments revealed non-trivial band topology for magnons and spin–orbit excitons (SOEs) in a quantum magnet CoTiO 3 (CTO). Here, we report phonon properties resulting from a combination of strong spin–orbit coupling, large crystal field splitting, and trigonal distortion in CTO. Specifically, the interaction between SOEs and phonons endows chirality to two E g phonon modes and leads to large phonon magnetic moments observed in magneto-Raman spectra. The remarkably strong magneto-phononic effect originates from the hybridization of SOEs and phonons due to their close energy proximity. While chiral phonons have been associated with electronic topology in some materials, our work suggests opportunities may arise by exploring chiral phonons coupled to topological bosons.
28
Rich, Christopher C., and Renee R. Frontiera. "Vibronic Coupling and Exciton Chirality: Electronic and Structural Rearrangement between Helical to Zero Momentum Molecular Exciton States." Journal of Physical Chemistry C, September 22, 2021. http://dx.doi.org/10.1021/acs.jpcc.1c05827.
29
Lu, Ying, Qian Wang, Lei Han, Yuzhen Zhao, Zemin He, Wenqi Song, Cheng Song, and Zongcheng Miao. "Spintronic Phenomena and Applications in Hybrid Organic–Inorganic Perovskites." Advanced Functional Materials, March 2024. http://dx.doi.org/10.1002/adfm.202314427.
Анотація:
AbstractThe spin degree of freedom in hybrid organic–inorganic perovskites (HOIPs) has become a rapidly growing research topic in both HOIPs and spintronics fields due to its fundamental scientific significance and tight relevance with optoelectronics. The flourishing achievements of HOIP spintronics call for a timely review to summarize the key progress and guide future developments. In this review, classical spintronic phenomena based on spin‐orbit coupling (SOC) are discussed, especially Rashba splitting and related applications such as spin‐charge conversion. Owing to the unique chirality‐spin coupling, spintronics in chiral HOIPs are particularly focused on, including chirality‐induced spin selectivity (CISS). Based on the complex band structure and carrier/exciton, spin dynamics is also widely investigated and constitutes an indispensable part of HOIP spintronics. Aside from the three main threads, other spintronic phenomena such as magneto‐optical coupling and device exploration are involved as promising opportunities. Despite the continuous breakthroughs in HOIP spintronics, more efforts are required to expand material systems, explore new physics, and optimize device configurations for enhanced performance and high integration. A deep understanding of spin behaviors in HOIPs will create a new platform beyond conventional optoelectronic and photovoltaic applications.
30
Mukhina, Maria. "Bringing chiral functionality to in vivo applications of nanomaterials." Light: Science & Applications 11, no. 1 (May 27, 2022). http://dx.doi.org/10.1038/s41377-022-00841-5.
Анотація:
AbstractChirality is a universal property of an endless number of objects in the universe. Nanotechnology is rapidly expanding to find ways to introduce chirality to artificial nanostructures. In a recent publication in Light: Science and Applications, Das et al. have successfully used capping with chiral ligand molecules to obtain chiral carbon dots. The authors provide a theoretical model to describe the origin of chirality in carbon dots as arising due to exciton coupling in a pair of chiral chromophores. Due to non-toxic chemical composition and sizes as small as 2–5 nm, the chiral carbon dots have the potential to outperform other chiral nanostructures in numerous biomedical applications. However, similarly to chiral drugs, their chiral toxicity must be well understood before the carbon dots are brought to living systems.
31
Deng, Xuyan, Li Junqiang, Lei Jin, Yilin Wang, Kun Liang, and Li Yu. "Plexcitonic optical chirality in the chiral plasmonic structure-microcavity-exciton strong coupling system." Optics Express, August 30, 2023. http://dx.doi.org/10.1364/oe.496182.
32
Wu, Fan, Jiaqi Guo, Yuming Huang, Kun Liang, Lei Jin, Junqiang Li, Xuyan Deng, et al. "Plexcitonic Optical Chirality: Strong Exciton–Plasmon Coupling in Chiral J-Aggregate-Metal Nanoparticle Complexes." ACS Nano, December 28, 2020. http://dx.doi.org/10.1021/acsnano.0c08274.
33
Ikeshita, Masahiro, Ayumu Kuroda, Seika Suzuki, Yoshitane Imai, and Takashi Tsuno. "Switching of Circularly Polarized Luminescence via Dynamic Axial Chirality Control of Chiral Bis(Boron difluoride) Complexes with Salen Ligands." ChemPhotoChem, May 22, 2024. http://dx.doi.org/10.1002/cptc.202400110.
Анотація:
The intensity and handedness of circularly polarized luminescence (CPL) have been successfully controlled by dynamic molecular motion in the solution state. Bis(boron difluoride) complexes with chiral salen ligands were synthesized and their photophysical properties were investigated. While these complexes showed rapid molecular rotation about the C‐N bond axis in solution at room temperature, two conformers assigned as atropisomers were observed in the NMR spectra at low temperature. Furthermore, the equilibrium of these atropisomers was found to change depending on the external environment, such as solvent and temperature, allowing the precise control of intensity and handedness of CPL without luminescence color shifts. Theoretical calculations based on density functional theory (DFT) revealed that intramolecular chiral exciton coupling is the key to the changes in the CPL properties.
34
Otsuka, Keigo, Nan Fang, Daiki Yamashita, Takashi Taniguchi, Kenji Watanabe, and Yuichiro K. Kato. "Deterministic transfer of optical-quality carbon nanotubes for atomically defined technology." Nature Communications 12, no. 1 (May 25, 2021). http://dx.doi.org/10.1038/s41467-021-23413-4.
Анотація:
AbstractWhen continued device scaling reaches the ultimate limit imposed by atoms, technology based on atomically precise structures is expected to emerge. Device fabrication will then require building blocks with identified atomic arrangements and assembly of the components without contamination. Here we report on a versatile dry transfer technique for deterministic placement of optical-quality carbon nanotubes. Single-crystalline anthracene is used as a medium which readily sublimes by mild heating, leaving behind clean nanotubes and thus enabling bright photoluminescence. We are able to position nanotubes of a desired chirality with a sub-micron accuracy under in-situ optical monitoring, thereby demonstrating deterministic coupling of a nanotube to a photonic crystal nanobeam cavity. A cross junction structure is also designed and constructed by repeating the nanotube transfer, where intertube exciton transfer is observed. Our results represent an important step towards development of devices consisting of atomically precise components and interfaces.
35
Grebenchuk, Sergey, Conor McKeever, Magdalena Grzeszczyk, Zhaolong Chen, Makars Šiškins, Arthur R. C. McCray, Yue Li, et al. "Topological Spin Textures in an Insulating van der Waals Ferromagnet." Advanced Materials, February 2, 2024. http://dx.doi.org/10.1002/adma.202311949.
Анотація:
AbstractGeneration and control of topological spin textures constitutes one of the most exciting challenges of modern spintronics given their potential applications in information storage technologies. Of particular interest are magnetic insulators, which due to low damping, absence of Joule heating and reduced dissipation could provide energy‐efficient spin‐textures platform. Here we demonstrate that the interplay between sample thickness, external magnetic fields and optical excitations can generate a prolific paramount of spin textures, and their coexistence in insulating CrBr3 van der Waals (vdW) ferromagnets. Using high‐resolution magnetic force microscopy and large‐scale micromagnetic simulation methods, we demonstrate the existence of a large region in T‐B phase diagram where different stripe domains, skyrmion crystals and magnetic domains exist and can be intrinsically selected or transformed to each‐other via a phase‐switch mechanism. Lorentz transmission electron microscopy unveiled the mixed chirality of the magnetic textures which are of Bloch‐type at given conditions but can be further manipulated into Néel‐type or hybrid‐type via thickness‐engineering. The topological phase transformation between the different magnetic objects could be further inspected by standard photoluminescence optical probes resolved by circular polarization indicative of an existance of exciton‐skyrmion coupling mechanism. Our findings identified vdW magnetic insulators as a promising framework of materials for the manipulation and generation of highly ordered skyrmion lattices relevant for device integration at the atomic level.This article is protected by copyright. All rights reserved
36
Wang, Haizhen, Yingying Chen, and Dehui Li. "Two/Quasi-two-dimensional Perovskite-based Heterostructures: Construction, Properties and Applications." International Journal of Extreme Manufacturing, December 13, 2022. http://dx.doi.org/10.1088/2631-7990/acab40.
Анотація:
Abstract Two-dimensional (2D)/quasi-2D organic-inorganic halide perovskites are regarded as naturally formed multiple quantum wells with inorganic layers isolated by long organic chains, which exhibit layered structure, large exciton binding energy, strong nonlinear optical effect, tunable bandgap via changing the layer number or chemical composition, improved environmental stability and excellent optoelectronic properties. The extensive choice of long organic chains endows 2D/quasi-2D perovskites with tunable electron-phonon coupling strength, chirality or ferroelectricity properties. In particular, the layered nature of 2D/quasi-2D perovskites allows us to exfoliate them to thin plates to integrate with other materials to form heterostructures, the fundamental structural units for optoelectronic devices, which would greatly extend the functionalities in view of the diversity of 2D/quasi-2D perovskites. In this paper, the recent achievements of 2D/quasi-2D perovskite-based heterostructures are reviewed. First, the structure and physical properties of 2D/quasi-2D perovskites are introduced. We then discuss the construction and characterization of 2D/quasi-2D perovskite-based heterostructures and highlight the prominent optical properties of the constructed heterostructures. Further, the potential applications of 2D/quasi-2D perovskite-based heterostructures in photovoltaic devices, light emitting devices, photodetectors/phototransistors and valleytronic devices are demonstrated. Finally, we summarize the current challenges and propose further research directions in the field of 2D/quasi-2D perovskite-based heterostructures.
37
Stamatopoulou, Elli, Sotiris Droulias, Guillermo Acuna, N. Asger Mortensen, and Christos Tserkezis. "Reconfigurable chirality with achiral excitonic materials in the strong-coupling regime." Nanoscale, 2022. http://dx.doi.org/10.1039/d2nr05063c.
Анотація:
We introduce and theoretically analyze the concept of manipulating optical chirality via strong coupling of the optical modes of chiral nanostructures with excitonic transitions in molecular layers or semiconductors. With...
38
Salij, Andrew H., Randall H. Goldsmith, and Roel Tempelaar. "Theory predicts 2D chiral polaritons based on achiral Fabry–Pérot cavities using apparent circular dichroism." Nature Communications 15, no. 1 (January 6, 2024). http://dx.doi.org/10.1038/s41467-023-44523-1.
Анотація:
AbstractRealizing polariton states with high levels of chirality offers exciting prospects for quantum information, sensing, and lasing applications. Such chirality must emanate from either the involved optical resonators or the quantum emitters. Here, we theoretically demonstrate a rare opportunity for realizing polaritons with so-called 2D chirality by strong coupling of the optical modes of (high finesse) achiral Fabry–Pérot cavities with samples exhibiting “apparent circular dichroism” (ACD). ACD is a phenomenon resulting from an interference between linear birefringence and dichroic interactions. By introducing a quantum electrodynamical theory of ACD, we identify the design rules based on which 2D chiral polaritons can be produced, and their chirality can be optimized.
39
Tang, Bing, Shixun Wang, Haochen Liu, Nanli Mou, Arsenii S. Portniagin, Peigang Chen, Ye Wu, Xiaoqing Gao, Dangyuan Lei, and Andrey L. Rogach. "Chiral Ligand‐Induced Inversion and Tuning of Excitonic Optical Activity in Intrinsically Chiral CsPbBr3 Perovskite Nanoplatelets." Advanced Optical Materials, August 23, 2023. http://dx.doi.org/10.1002/adom.202301524.
Анотація:
AbstractOwing to their attractive optical and chiroptical properties, chiral metal halide perovskites have received increasing attention, with potential applications ranging from photonics and optoelectronics to spintronics. Metal halide perovskite nanocrystals with either intrinsic or extrinsic (e.g., chiral ligand‐induced) chirality have been reported recently, and the interplay between these two types of chirality has yet to be addressed. Herein, the inversion and tuning of excitonic optical activity is reported in intrinsically chiral perovskite nanoplatelets, originating from interactions between their structural chirality (due to the spontaneously formed screw dislocations in the crystalline lattice) and the surface enantiomeric (R/S) chiral ligands R/S‐phenylethylammonium bromide. Through post‐preparative exposure of the perovskite nanoplatelets to these R/S ligands of varied contents, either chiral ligand‐induced intrinsic chirality inversion or negative and positive Cotton effects induced by the ligands via electronic coupling between the ligand and the nanoplatelets are identified. These findings deepen understanding of the modulation of excitonic optical activity in chiral perovskites and can guide the rational design and synthesis of novel chiral materials.
40
Doležal, Jiří, Sofia Canola, Prokop Hapala, Rodrigo Cezar de Campos Ferreira, Pablo Merino, and Martin Švec. "Evidence of exciton-libron coupling in chirally adsorbed single molecules." Nature Communications 13, no. 1 (October 12, 2022). http://dx.doi.org/10.1038/s41467-022-33653-7.
Анотація:
AbstractInterplay between motion of nuclei and excitations has an important role in molecular photophysics of natural and artificial structures. Here we provide a detailed analysis of coupling between quantized librational modes (librons) and charged excited states (trions) on single phthalocyanine dyes adsorbed on a surface. By means of tip-induced electroluminescence performed with a scanning probe microscope, we identify libronic signatures in spectra of chirally adsorbed phthalocyanines and find that these signatures are absent from spectra of symmetrically adsorbed species. We create a model of the libronic coupling based on the Franck-Condon principle to simulate the spectral features. Experimentally measured librational spectra match very well the theoretically calculated librational eigenenergies and peak intensities (Franck-Condon factors). Moreover, the comparison reveals an unexpected depopulation channel for the zero libron of the excited state that can be effectively controlled by tuning the size of the nanocavity. Our results showcase the possibility of characterizing the dynamics of molecules by their low-energy molecular modes using µeV-resolved tip-enhanced spectroscopy.
41
Wang, Yuan, Dian Niu, Guanghui Ouyang та Minghua Liu. "Double helical π-aggregate nanoarchitectonics for amplified circularly polarized luminescence". Nature Communications 13, № 1 (31 березня 2022). http://dx.doi.org/10.1038/s41467-022-29396-0.
Анотація:
AbstractThe canonical double helical π-stacked array of base pairs within DNA interior has inspired the interest in supramolecular double helical architectures with advanced electronic, magnetic and optical functions. Here, we report a selective-recognized and chirality-matched co-assembly strategy for the fabrication of fluorescent π-amino acids into double helical π-aggregates, which show exceptional strong circularly polarized luminescence (CPL). The single crystal structure of the optimal combination of co-assemblies shows that the double-stranded helical organization of these π-amino acids is cooperatively assisted by both CH-π and hydrogen-bond arrays with chirality match. The well-defined spatial arrangement of the π-chromophores could effectively suppress the non-radiative decay pathways and facilitate chiral exciton couplings, leading to superior CPL with a strong figure of merit (glum = 0.14 and QY = 0.76). Our findings might open a new door for developing DNA-inspired chiroptical materials with prominent properties by enantioselective co-assembly initiated double helical π-aggregation.
42
Hasegawa, Masashi, та Yasuhiro Mazaki. "Stereogenic π-Conjugated Macrocycles: Synthesis, Structure, and Chiroptical Properties Including Circularly Polarized Luminescence". Synlett, 22 серпня 2023. http://dx.doi.org/10.1055/a-2158-8820.
Анотація:
Highly symmetrical and aesthetically pleasing molecules have attracted the attention of organic chemists. We synthesized new highly symmetric stereogenic π-conjugated macrocycles with planar or axial chirality. Macrocyclic oligomers synthesized by Yamamoto coupling or Suzuki-Miyaura cross-coupling from the π-unit containing chirality. These cyclization reactions gave multiple oligomers in relatively high yields. We then elucidated their structures and investigated their chiroptical properties, including circular dichroism (CD) and circularly polarized luminescence (CPL). Because of the selection rule for rigid and symmetric structures, these macrocycles exhibit a high dissymmetry factor (gabs or glum) for circularly polarized light in CD or CPL. Several rigid cyclic compounds retain a highly symmetric structure in the excited state and exhibit higher glum values than common chiral organic compounds. This account provides a brief background regarding chiroptical properties, followed by a summary of the various macrocycles synthesized in this study. We are glad if this account will be a source of ideas not only for chemists working with π-conjugated compounds, but also for synthetic chemists working with chiral compounds, especially those engaged in asymmetric synthesis.
43
Pikulski, Marek, Toni Shiroka, Francesco Casola, Arneil P. Reyes, Philip L. Kuhns, Shuang Wang, Hans-Rudolf Ott, and Joël Mesot. "Two coupled chains are simpler than one: field-induced chirality in a frustrated spin ladder." Scientific Reports 10, no. 1 (September 28, 2020). http://dx.doi.org/10.1038/s41598-020-72215-z.
Анотація:
Abstract Although the frustrated (zigzag) spin chain is the Drosophila of frustrated magnetism, our understanding of a pair of coupled zigzag chains (frustrated spin ladder) in a magnetic field is still lacking. We address this problem through nuclear magnetic resonance (NMR) experiments on BiCu$$_2$$ 2 PO$$_6$$ 6 in magnetic fields up to 45 T, revealing a field-induced spiral magnetic structure. Conjointly, we present advanced numerical calculations showing that even a moderate rung coupling dramatically simplifies the phase diagram below half-saturation magnetization by stabilizing a field-induced chiral phase. Surprisingly for a one-dimensional model, this phase and its response to Dzyaloshinskii-Moriya (DM) interactions adhere to classical expectations. While explaining the behavior at the highest accessible magnetic fields, our results imply a different origin for the solitonic phases occurring at lower fields in BiCu$$_2$$ 2 PO$$_6$$ 6 . An exciting possibility is that the known, DM-mediated coupling between chirality and crystal lattice may give rise to a new kind of spin-Peierls instability.
44
Jana, Sankar, Kwang-Hwan Jung, and Mordechai Sheves. "The chirality origin of retinal-carotenoid complex in gloeobacter rhodopsin: a temperature-dependent excitonic coupling." Scientific Reports 10, no. 1 (August 19, 2020). http://dx.doi.org/10.1038/s41598-020-70697-5.
45
Lima Fernandes, Imara, Stefan Blügel, and Samir Lounis. "Spin-orbit enabled all-electrical readout of chiral spin-textures." Nature Communications 13, no. 1 (March 24, 2022). http://dx.doi.org/10.1038/s41467-022-29237-0.
Анотація:
AbstractChirality and topology are intimately related fundamental concepts, which are heavily explored to establish spin-textures as potential magnetic bits in information technology. However, this ambition is inhibited since the electrical reading of chiral attributes is highly non-trivial with conventional current perpendicular-to-plane (CPP) sensing devices. Here we demonstrate from extensive first-principles simulations and multiple scattering expansion the emergence of the chiral spin-mixing magnetoresistance (C-XMR) enabling highly efficient all-electrical readout of the chirality and helicity of respectively one- and two-dimensional magnetic states of matter. It is linear with spin-orbit coupling in contrast to the quadratic dependence associated with the unveiled non-local spin-mixing anisotropic MR (X-AMR). Such transport effects are systematized on various non-collinear magnetic states – spin-spirals and skyrmions – and compared to the uncovered spin-orbit-independent multi-site magnetoresistances. Owing to their simple implementation in readily available reading devices, the proposed magnetoresistances offer exciting and decisive ingredients to explore with all-electrical means the rich physics of topological and chiral magnetic objects.
46
Aceves Rodriguez, Uriel A., Filipe Souza Mendes Guimarães, Sascha Brinker, and Samir Lounis. "Magnetic exchange interactions at the proximity of a superconductor." Journal of Physics: Condensed Matter, March 12, 2024. http://dx.doi.org/10.1088/1361-648x/ad32de.
Анотація:
Abstract Interfacing magnetism with superconductivity gives rise to a wonderful playground for intertwining key degrees of freedom: Cooper pairs, spin, charge, and spin-orbit interaction, from which emerge 
a wealth of exciting phenomena, fundamental in the nascent field of superconducting spinorbitronics and topological quantum technologies. Magnetic exchange interactions (MEI), being isotropic or chiral such as the Dzyaloshinskii-Moriya interactions (DMI), are vital in establishing the magnetic behavior at these interfaces as well as in dictating not only complex transport phenomena, but also the manifestation of topologically trivial or non-trivial objects. Here, we propose a methodology enabling the extraction of the tensor of MEI from electronic structure simulations accounting for superconductivity. We apply our scheme to the case of a Mn layer deposited on Nb(110) surface and explore proximity-induced impact on the MEI. The latter are weakly modified by a realistic electron-phonon coupling. However, tuning the superconducting order parameter, we unveil potential change of the magnetic order accompanied with chirality switching, as induced by the interplay of spin-orbit interaction and Cooper pairing. Owing to its simple formulation, our methodology can be readily implemented in state-of-the-art frameworks capable of tackling superconductivity and magnetism. We thus foresee implications in the simulations and prediction of topological superconducting bits as well as \new{of} cryogenic superconducting hybrid devices involving magnetic units.
47
Gross, Franz, Eberhard Klempt, Stanley J. Brodsky, Andrzej J. Buras, Volker D. Burkert, Gudrun Heinrich, Karl Jakobs, et al. "50 Years of quantum chromodynamics." European Physical Journal C 83, no. 12 (December 12, 2023). http://dx.doi.org/10.1140/epjc/s10052-023-11949-2.
Анотація:
AbstractQuantum Chromodynamics, the theory of quarks and gluons, whose interactions can be described by a local SU(3) gauge symmetry with charges called “color quantum numbers”, is reviewed; the goal of this review is to provide advanced Ph.D. students a comprehensive handbook, helpful for their research. When QCD was “discovered” 50 years ago, the idea that quarks could exist, but not be observed, left most physicists unconvinced. Then, with the discovery of charmonium in 1974 and the explanation of its excited states using the Cornell potential, consisting of the sum of a Coulomb-like attraction and a long range linear confining potential, the theory was suddenly widely accepted. This paradigm shift is now referred to as the November revolution. It had been anticipated by the observation of scaling in deep inelastic scattering, and was followed by the discovery of gluons in three-jet events. The parameters of QCD include the running coupling constant, $$\alpha _s(Q^2)$$ α s ( Q 2 ) , that varies with the energy scale $$Q^2$$ Q 2 characterising the interaction, and six quark masses. QCD cannot be solved analytically, at least not yet, and the large value of $$\alpha _s$$ α s at low momentum transfers limits perturbative calculations to the high-energy region where $$Q^2\gg \varLambda _{{\textrm{QCD}}} ^2\simeq $$ Q 2 ≫ Λ QCD 2 ≃ (250 MeV)$$^2$$ 2 . Lattice QCD (LQCD), numerical calculations on a discretized space-time lattice, is discussed in detail, the dynamics of the QCD vacuum is visualized, and the expected spectra of mesons and baryons are displayed. Progress in lattice calculations of the structure of nucleons and of quantities related to the phase diagram of dense and hot (or cold) hadronic matter are reviewed. Methods and examples of how to calculate hadronic corrections to weak matrix elements on a lattice are outlined. The wide variety of analytical approximations currently in use, and the accuracy of these approximations, are reviewed. These methods range from the Bethe–Salpeter, Dyson–Schwinger coupled relativistic equations, which are formulated in both Minkowski or Euclidean spaces, to expansions of multi-quark states in a set of basis functions using light-front coordinates, to the AdS/QCD method that imbeds 4-dimensional QCD in a 5-dimensional deSitter space, allowing confinement and spontaneous chiral symmetry breaking to be described in a novel way. Models that assume the number of colors is very large, i.e. make use of the large $$N_c$$ N c -limit, give unique insights. Many other techniques that are tailored to specific problems, such as perturbative expansions for high energy scattering or approximate calculations using the operator product expansion are discussed. The very powerful effective field theory techniques that are successful for low energy nuclear systems (chiral effective theory), or for non-relativistic systems involving heavy quarks, or the treatment of gluon exchanges between energetic, collinear partons encountered in jets, are discussed. The spectroscopy of mesons and baryons has played an important historical role in the development of QCD. The famous X,Y,Z states – and the discovery of pentaquarks – have revolutionized hadron spectroscopy; their status and interpretation are reviewed as well as recent progress in the identification of glueballs and hybrids in light-meson spectroscopy. These exotic states add to the spectrum of expected $$q{{\bar{q}}}$$ q q ¯ mesons and qqq baryons. The progress in understanding excitations of light and heavy baryons is discussed. The nucleon as the lightest baryon is discussed extensively, its form factors, its partonic structure and the status of the attempt to determine a three-dimensional picture of the parton distribution. An experimental program to study the phase diagram of QCD at high temperature and density started with fixed target experiments in various laboratories in the second half of the 1980s, and then, in this century, with colliders. QCD thermodynamics at high temperature became accessible to LQCD, and numerical results on chiral and deconfinement transitions and properties of the deconfined and chirally restored form of strongly interacting matter, called the Quark–Gluon Plasma (QGP), have become very precise by now. These results can now be confronted with experimental data that are sensitive to the nature of the phase transition. There is clear evidence that the QGP phase is created. This phase of QCD matter can already be characterized by some properties that indicate, within a temperature range of a few times the pseudocritical temperature, the medium behaves like a near ideal liquid. Experimental observables are presented that demonstrate deconfinement. High and ultrahigh density QCD matter at moderate and low temperatures shows interesting features and new phases that are of astrophysical relevance. They are reviewed here and some of the astrophysical implications are discussed. Perturbative QCD and methods to describe the different aspects of scattering processes are discussed. The primary parton–parton scattering in a collision is calculated in perturbative QCD with increasing complexity. The radiation of soft gluons can spoil the perturbative convergence, this can be cured by resummation techniques, which are also described here. Realistic descriptions of QCD scattering events need to model the cascade of quark and gluon splittings until hadron formation sets in, which is done by parton showers. The full event simulation can be performed with Monte Carlo event generators, which simulate the full chain from the hard interaction to the hadronic final states, including the modelling of non-perturbative components. The contribution of the LEP experiments (and of earlier collider experiments) to the study of jets is reviewed. Correlations between jets and the shape of jets had allowed the collaborations to determine the “color factors” – invariants of the SU(3) color group governing the strength of quark–gluon and gluon–gluon interactions. The calculated jet production rates (using perturbative QCD) are shown to agree precisely with data, for jet energies spanning more than five orders of magnitude. The production of jets recoiling against a vector boson, $$W^\pm $$ W ± or Z, is shown to be well understood. The discovery of the Higgs boson was certainly an important milestone in the development of high-energy physics. The couplings of the Higgs boson to massive vector bosons and fermions that have been measured so far support its interpretation as mass-generating boson as predicted by the Standard Model. The study of the Higgs boson recoiling against hadronic jets (without or with heavy flavors) or against vector bosons is also highlighted. Apart from the description of hard interactions taking place at high energies, the understanding of “soft QCD” is also very important. In this respect, Pomeron – and Odderon – exchange, soft and hard diffraction are discussed. Weak decays of quarks and leptons, the quark mixing matrix and the anomalous magnetic moment of the muon are processes which are governed by weak interactions. However, corrections by strong interactions are important, and these are reviewed. As the measured values are incompatible with (most of) the predictions, the question arises: are these discrepancies first hints for New Physics beyond the Standard Model? This volume concludes with a description of future facilities or important upgrades of existing facilities which improve their luminosity by orders of magnitude. The best is yet to come!