Relevant bibliographies by topics / Laser excitation mechanisms

Academic literature on the topic 'Laser excitation mechanisms'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Laser excitation mechanisms"

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Жукавин, Р. Х. "Терагерцовое стимулированное излучение при оптическом резонансном возбуждении германия, легированного мелкими донорами." Физика и техника полупроводников 55, no. 9 (2021): 729. http://dx.doi.org/10.21883/ftp.2021.09.51285.12.

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The mechanisms responsible for terahertz stimulated radiation under resonant intracenter excitation of shallow donors in bulk germanium are considered to be the inversion laser mechanism (ILM) and electron stimulated Raman scattering (e-SRS). The e-SRS cross-section was estimated in the case of resonant excitation of odd levels of a shallow arsenic donor in germanium. The output intensity under resonant excitation of germanium doped with arsenic is calculated. It is shown that at an intensity exceeding the threshold for e-SRS, there should be a competition of mechanisms leading to a decrease in the intensity of ILM, which can be detected by the dependence of the output intensity on time.
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Wu, Xiaojun, Xiaoshu Chen, Fuli Zhao, Tianqing Jia, and Gang Wang. "Terahertz Radiation Mechanisms in ZnSe at Femtosecond Laser Pulse Excitation." Japanese Journal of Applied Physics 46, no. 4A (April 5, 2007): 1497–500. http://dx.doi.org/10.1143/jjap.46.1497.

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Sobral, H., M. Raineri, D. Schinca, M. Gallardo, and R. Duchowicz. "Excitation mechanisms and characterization of a multi-ionic xenon laser." IEEE Journal of Quantum Electronics 35, no. 9 (1999): 1308–13. http://dx.doi.org/10.1109/3.784590.

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Seltzer, M. D., and R. B. Green. "Laser-Power Dependency of Resonant Two-Photon Ionization in Flames." Applied Spectroscopy 43, no. 4 (May 1989): 633–37. http://dx.doi.org/10.1366/0003702894202436.

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Resonant two-photon ionization competes with laser-enhanced collisional ionization (LEI) in flames to ionize analyte atoms. The predominance of either mechanism for a given element depends on the excitation scheme as well as the level of irradiance. Optical saturation of the resonant transition through which the two-photon mechanism proceeds precludes observation of a second-order dependence of ionization signal on laser power. The laser power dependency of resonant two-photon ionization for a series of elements is examined, and results of diagnostic value regarding the probable ionization mechanisms are obtained.
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Liu, Zeming, Guy Vitrant, Yaya Lefkir, Said Bakhti, and Nathalie Destouches. "Laser induced mechanisms controlling the size distribution of metallic nanoparticles." Physical Chemistry Chemical Physics 18, no. 35 (2016): 24600–24609. http://dx.doi.org/10.1039/c6cp03415b.

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Zhang, Hongxin, Tianqing Jia, Xiaoying Shang, Shian Zhang, Zhenrong Sun, and Jianrong Qiu. "Mechanisms of the blue emission of NaYF4:Tm3+ nanoparticles excited by an 800 nm continuous wave laser." Physical Chemistry Chemical Physics 18, no. 37 (2016): 25905–14. http://dx.doi.org/10.1039/c6cp04413a.

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Simultaneous multiwavelength excitation and the quantum transition principle are utilized to study the blue emission mechanisms of NaYF4:Tm3+ UCNPs under 800 nm CW laser excitation.
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Haglund, Richard F. "Damage Mechanisms in Optical Materials For High-Power, Short-Wavelength Laser Systems." MRS Bulletin 11, no. 3 (June 1986): 46–47. http://dx.doi.org/10.1557/s088376940005483x.

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Damage to optical materials under intense photon irradiation has always been a major problem in the design and operation of high-energy and high-average-power lasers. In short-wavelength lasers, operating at visible and ultraviolet wavelengths, the problem appears to be especially acute; presently attainable damage thresholds seriously compromise the engineering design of laser windows and mirrors, pulsed power trains and oscillator-amplifier systems architecture. Given the present interest in ultraviolet excimer lasers and in short-pulse, high-power free-electron lasers operating at visible and shorter wavelengths, the “optical damage problem” poses a scientific and technological challenge of significantdimensions. The solution of this problem even has significant implications outside the realm of lasers, for example, in large space-borne systems (such as the Hubble Telescope) exposed to intense ultraviolet radiation.The dimensions of the problem are illustrated by the Large-Aperture krypton-fluoride laser amplifier Module (LAM) shown schematically in Figure 1. This device, now operating at the Los Alamos National Laboratory, is typical of current and planned large excimer lasers for fusion applications. The LAM has an active volume of some 2 m3, and optical surfaces (resonator mirror and windows) exceeding 1 m2 in size; the fabrication of these optical elements was the most expensive and time-consuming single item in the construction of the laser. During laser operation, a population inversion in an Ar-Kr-F2 mix ture is created through electron-beam excitation of the laser gas by two 400 kA beams of 650 keV electrons from a cold cathode discharge. The electron trajectories in the gas are constrained by a 4 kG magnetic field transverse to the optical axis produced by a pair of large Helmholtzcoils.
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Егоров, Ф. А., and В. Т. Потапов. "Лазерное возбуждение крутильных колебаний волоконных микросветоводов." Письма в журнал технической физики 45, no. 4 (2019): 55. http://dx.doi.org/10.21883/pjtf.2019.04.47341.17353.

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AbstractComparative analysis of mechanisms of the laser excitation of torsional vibration modes in optical microfibers shows that special attention should be devoted to the Sadovsky effect manifested in polarization-anisotropic optical microfibers. Estimations of the efficiency of this mechanism for the excitation of torsional vibrations and polarization modulation in the proposed types of anisotropic quartz microfibers shows the possibility of creating new types of polarization elements—optically controlled fiber polarization devices and sensitive elements for resonance fiber-optic sensors.
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Shang, Xiaoying, Ping Chen, Tianqing Jia, Donghai Feng, Shian Zhang, Zhenrong Sun, and Jianrong Qiu. "Upconversion luminescence mechanisms of Er3+ ions under excitation of an 800 nm laser." Physical Chemistry Chemical Physics 17, no. 17 (2015): 11481–89. http://dx.doi.org/10.1039/c5cp00057b.

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PATEL, DARAYAS, CALVIN VANCE, NEWTON KING, MALCOLM JESSUP, LEKARA GREEN, and SERGEY SARKISOV. "STRONG VISIBLE UPCONVERSION IN RARE EARTH ION-DOPED NaYF4 CRYSTALS." Journal of Nonlinear Optical Physics & Materials 19, no. 02 (June 2010): 295–301. http://dx.doi.org/10.1142/s0218863510005133.

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NaYF 4: Er 3+, Yb 3+ crystals were prepared by simple synthetic method. Under 980 nm laser excitation, 408 nm, 539 nm and 655 nm upconversion emissions were recorded. Laser power and signal intensities of the upconverted emissions were obtained to understand the upconversion mechanisms.
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Dissertations / Theses on the topic "Laser excitation mechanisms"

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Sang, Robert Thomas, and n/a. "Superelastic Electron Scattering from Laser Excited States of Sodium." Griffith University. School of Science, 1995. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050921.120911.

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This thesis presents the results of a series of experiments in which electrons are superelastically scattered from various laser excited states of sodium. The atoms, once in the optically prepared state, are forced to relax via the superelastic collision with an electron. The rate of detection of superelastically scattered electrons was measured as a function of the laser polarisation which enabled pseudo Stokes parameters to be determined. These pseudo Stokes parameters are functions of both optical pumping parameters and atomic collision parameters. The optical pumping parameters describe the laser-atom interaction and the atomic collision parameters describe the electron-atom collision process. Three different laser excitation mechanisms were used to optically pump the atoms into various excited states. The first of these used a single laser tuned to the 32S 112(F'=2 hyperfine state)-~32P312 transition. The excited atoms underwent a superelastic collision with an electron leaving the atom in the ground state and pseudo Stokes parameters were measured as a function of both scattering angle and incident electron energy. The second superelastic experiment, utilised a folded step excitation mechanism which employed two lasers tuned from the two hypethne states of the 32S112 ground state respectively to the 32P312 excited state. Power broadening effects in the single laser experiment cause the atoms to be optically pumped into the F= 1 hyperfine ground state. The laser powers used were not great enough to power broaden the hyperfine ground states and as such the F'= 1 sublevel effectively acted as a sink. The folded step excitation method enabled the excited state population to be increased so that data at larger scattering angles could be obtained. Stokes parameters from both of these experiments which had an incident energy range of 10eV to 30eV and an angular range of 5°-25° were compared to three current electron-atom scattering theories and previous experimental data. Overall, fair to good agreement was found between theory and experiments for the individual Stokes parameters. Losses of coherence was observed at small scattering angles (50.200) at 20eV and 25eV incident electron energies which were poorly modelled by the three different theories. The third superelastic experiment involved the use of two lasers of specified polarisation to stepwise excite the atoms to the 32D512 excited state. Superelastic collisions with incident electron energies of 20eV from the 32D512-*32P312~312 collision were studied at three different scattering angles and pseudo Stokes parameters for the case where the polarisations of the radiation from the lasers were parallel were measured. The single step and folded step laser-atom interactions for it excitation were modelled using a full quantum electrodynamical treatment so that the optical pumping parameters from the single and folded step experiments could be investigated. Equations of motion were derived in the Heisenberg picture and it is shown that for the single laser case 59 equations of motion are required to fully model the interaction and for the folded step ease 78 equations of motion are required. The results of calculations demonstrated that the optical pumping parameters were sensitive to laser intensity, laser detuning and the Doppler width of the atomic beam. The theoretical quantum electrodynamical calculation results were in good agreement with the experimental results.
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Kurucu, Salur Riza. "A New Design Of Excitation Mechanism To Be Exploited By Modern Rf Excited Co2 Lasers." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605394/index.pdf.

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On this thesis work, design and construction of an up to date complete RF excitation system was intended. This excitation system is mainly based on highly efficient switching power generators and proper coupling of the power to the object plasma. This new excitation system design should answer the demands of today'
s progressed CO2 lasers on various power ranges. Though it could be used by a large variety of applications including RF plasma and RF heating, on the first occasion in order to define design considerations, this system is to be exploited by RF excited fast flow and RF excited slab CO2 laser constructions.
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Vonderheide, Christopher M. "Laser velocimetric flow mapping and characterization of oil mist nozzles used for blade excitation in high cycle fatigue testing." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Sep%5FVonderheide.pdf.

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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, September 2005.
Thesis Advisor(s): Dr. Raymond Shreeve, Dr. Garth Hobson. Includes bibliographical references (p. 61). Also available online.
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Thompson, Andrew P. "Effect of pressure and temperature on oil mist sprays used for blade excitation in high cycle fatigue testing." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Jun%5FThompson_Andrew.pdf.

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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, June 2006.
Thesis Advisor(s): Raymond Shreeve. "June 2006." Includes bibliographical references (p. 131). Also available in print.
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Alibakhshikenari, M., B. S. Virdee, M. Khalily, C. H. See, Raed A. Abd-Alhameed, F. Falcone, T. A. Denidni, and E. Limiti. "High-Gain On-Chip Antenna Design on Silicon Layer with Aperture Excitation for Terahertz Applications." 2020. http://hdl.handle.net/10454/18476.

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No
This letter investigates the feasibility of designing a high gain on-chip antenna on silicon technology for subterahertz applications over a wide-frequency range. High gain is achieved by exciting the antenna using an aperture fed mechanism to couple electromagnetics energy from a metal slot line, which is sandwiched between the silicon and polycarbonate substrates, to a 15-element array comprising circular and rectangular radiation patches fabricated on the top surface of the polycarbonate layer. An open ended microstrip line, which is orthogonal to the metal slot-line, is implemented on the underside of the silicon substrate. When the open ended microstrip line is excited it couples the signal to the metal slot-line which is subsequently coupled and radiated by the patch array. Measured results show the proposed on-chip antenna exhibits a reflection coefficient of less than-10 dB across 0.290-0.316 THz with a highest gain and radiation efficiency of 11.71 dBi and 70.8%, respectively, occurred at 0.3 THz. The antenna has a narrow stopband between 0.292 and 0.294 THz. The physical size of the presented subterahertz on-chip antenna is 20 × 3.5 × 0.126 mm3.
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Books on the topic "Laser excitation mechanisms"

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Biswas, D. J. Light induced drift: A possible mechanism of separation of isotopes by laser excitation. Mumbai: Bhabha Atomic Research Centre, 2003.

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Asai, H. Theoretical Study of THz Emission from HTS Cuprate. Edited by A. V. Narlikar. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780198738169.013.9.

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This article examines the THz emission from high-temperature superconducting (HTS) cuprates in the mesoscopic state using the intrinsic Josephson junction model. Cuprate superconductors are high-temperature superconductors that exhibit exotic electromagnetic properties. One of the remarkable features of HTS cuprates is high anisotropy due to their layered structures. Almost all HTS cuprates are composed of stacks of CuO2 layers and blocking layers which supply charge carriers to the CuO2 layers. The crystal structures of the HTS cuprates naturally form Josephson junctions known as intrinsic Josephson junctions (IJJs). This article first describes the basic theory of IJJ and the mechanism of THz emission before discussing the effect of temperature inhomogeneity on the emission properties. It then introduces a novel IJJ-based THz emitter that utilizes laser heating. Theoretical results show that the THz emission is caused by the strong excitation of transverse Josephson plasma waves in IJJs under a direct current bias.
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Anderson, James A. Programming. Oxford University Press, 2018. http://dx.doi.org/10.1093/acprof:oso/9780199357789.003.0014.

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The author makes several suggestions for how to control the direction taken by an active cognitive process. He proposes a neural/cognitive programming mechanism: traveling waves on cortex. Evidence for traveling waves exists, and interactions of such waves have useful properties. One example is due to Pitts and McCulloch: Why are squares of different sizes seen as examples of squares? If excitation propagates from the corners of a square, waves meet at the diagonals. Squares of different sizes then have a common diagonal representation. Later models include “grassfire models” and “medial axis” models. Experiments suggests that response exists at a “medial axis” halfway between bounding contours, and in this approach “Identity” and “Symmetry” become the same computation. Traveling waves in audition can be used to give the pattern-dependent frequency independent responses seen in some kinds of speech perception.
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Book chapters on the topic "Laser excitation mechanisms"

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Hoheisel, W., M. Vollmer, and F. Träger. "Photodesorption of metal atoms by collective electron excitation." In Laser Ablation Mechanisms and Applications, 77–81. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/bfb0048355.

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Arakawa, E. T., I. Lee, and T. A. Callcottt. "Desorption of Al, Au, and Ag using surface plasmon excitation." In Laser Ablation Mechanisms and Applications, 82–86. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/bfb0048356.

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Lee, I., E. T. Arakawa, and T. A. Callcott. "Desorption of large organic molecules by laser-induced plasmon excitation." In Laser Ablation Mechanisms and Applications, 297–300. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/bfb0048385.

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Kim, HyunSook, and Henry Helvajian. "Threshold fluence UV laser excitation of W(100) and O2,H2,F/W(100): Photoejected ion KE distributions." In Laser Ablation Mechanisms and Applications, 87–95. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/bfb0048357.

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Bäuerle, Dieter. "Fundamental Excitation Mechanisms." In Chemical Processing with Lasers, 5–35. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-662-02505-5_2.

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Yassievich, I. N., A. S. Moskalenko, O. B. Gusev, and M. S. Bresler. "Excitation Mechanism of Er Photoluminescence in Bulk Si And SiO2 With Nanocrystals." In Towards the First Silicon Laser, 421–28. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-010-0149-6_36.

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Bader, Viktor, and Friedrich-Reinhard Grosche. "Control of flow separation by dynamic excitation of the free shear layer." In Notes on Numerical Fluid Mechanics (NNFM), 16–21. Wiesbaden: Vieweg+Teubner Verlag, 1999. http://dx.doi.org/10.1007/978-3-663-10901-3_3.

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Sun, M. B., Z. G. Wang, and J. H. Liang. "Mixing Enhancement of a 2D Supersonic Mixing Layer Induced by Inflow Periodic Temperature Excitation." In New Trends in Fluid Mechanics Research, 150–53. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-75995-9_38.

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Alaruri, Sami D. "A Step-Index Multimode Fiber-Optic Microbend Displacement Sensor Wavelength Dependent Loss." In Strategic Applications of Measurement Technologies and Instrumentation, 47–60. IGI Global, 2019. http://dx.doi.org/10.4018/978-1-5225-5406-6.ch003.

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In this chapter, the wavelength dependence of bend loss in a step-index multimode optical fiber (100 µm core diameter; fused silica) was investigated for fiber bend radii ranging between 2.0 and 4.5 mm using six laser excitation wavelengths, namely, 337.1, 470, 590, 632.8, 750, and 810 nm. The results obtained from fitting the bend loss measurements to Kao's model and utilizing MATLAB® indicate that bend loss is wavelength dependent and transmission loss in multimode optical fibers increases with the decrease in the fiber bend radius. Furthermore, the response of a microbend fiber-optic displacement sensor was characterized at 337.1, 470, 632.8, 750, and 810 nm. Measurements obtained from the microbend sensor indicate that the sensor output power is linear with the applied displacement and the sensor output is wavelength dependent. Lastly, references for industrial and biomedical applications of microbend fiber-optic sensors are provided. Finally, a brief description for the transmission loss mechanisms in optical fibers is given.
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Feng, Bo, Dario J. Pasadas, Artur L. Ribeiro, and Helena G. Ramos. "Eddy Current Testing of the Lightning Strike Protection Layer in Aerospace Composite Structures." In Studies in Applied Electromagnetics and Mechanics. IOS Press, 2020. http://dx.doi.org/10.3233/saem200004.

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The lightning strike protection layer, which is a mesh of metal stripes, is adhered to composite materials to dissipate the huge current induced during lightning strike. This paper presents an eddy current imaging method to inspect defects in the lightning strike protection layer. A tuning method was applied to tune the resonant frequency of excitation and sensing coils and enhance the testing results. Two parameters, namely the amplitude of induced voltage in the sensing coil and the amplitude of the voltage across a sampling resistor in the excitation circuit, were used to image the defects. The results show that the image formed by sensing coil voltage is less noisy and more accurate.
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Conference papers on the topic "Laser excitation mechanisms"

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Dirnberger, L., P. E. Dyer, S. R. Farrar, and P. H. Key. "Magnetic field enhanced excitation and ionization in excimer laser-ablation plumes." In Laser ablation: mechanisms and applications—II. AIP, 1993. http://dx.doi.org/10.1063/1.44880.

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Kim, HyunSook, and Henry Helvajian. "Laser-induced ion species ejection from thin silver films: influence of plasmon excitation on the desorbed species KE distributions." In Laser ablation: mechanisms and applications—II. AIP, 1993. http://dx.doi.org/10.1063/1.44884.

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Jiang, Lan, and Hai-Lung Tsai. "Modeling of CO2 Gas Excitation Under CO2 Laser Irradiation." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-15625.

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Lasers especially multiple laser beams demonstrate unique advantages as energy sources in diamond synthesis. However, the fundamental mechanisms involved in the laser-assisted processes are not Well understood. In a reported amazingly-fast multiple laser coating technique, CO2 gas is claimed as the sole precursor or secondary precursor, which remains poorly understood and unverified. The absorption coefficient changes under the irradiation of the multiple lasers are one of the keys to resolve the mysteries of multiple laser beam coating processes. This study investigates the optical absorption in CO2 gas at the CO2 laser wavelength. This resonance absorption process is modeled as an inverse process of the lasing transitions of CO2 lasers. The well-established CO2 vibrational-rotational energy structures are used as the basis for the calculations with the Boltzmann distribution for equilibrium states and the three-temperature model for non-equilibrium states. Based on the population distribution, our predictions of CO2 absorption coefficient changes as the function of temperature are in agreement with the published data.
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Haglund, Jr., Richard F., Daniel M. Bubb, David R. Ermer, G. K. Hubler, Eric J. Houser, James S. Horwitz, Borislav L. Ivanov, Michael R. Papantonakis, Bradley R. Ringeisen, and Kenneth E. Schriver. "Resonant infrared laser materials processing at high vibrational excitation density: applications and mechanisms." In Fourth International Symposium on laser Precision Microfabrication, edited by Isamu Miyamoto, Andreas Ostendorf, Koji Sugioka, and Henry Helvajian. SPIE, 2003. http://dx.doi.org/10.1117/12.541054.

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Gautier, Charles A., Olivier Albert, J. C. Loulergue, and Jean Etchepare. "Impulsive and/or spectral mechanisms associated with ultrashort pulses: phonon excitation and detection." In ICONO '98: Laser Spectroscopy and Optical Diagnostics--Novel Trends and Applications in Laser Chemistry, Biophysics, and Biomedicine, edited by Andrey Y. Chikishev, Victor N. Zadkov, and Alexei M. Zheltikov. SPIE, 1999. http://dx.doi.org/10.1117/12.339999.

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Wells, Jonathon, Chris Kao, Peter Konrad, Anita Mahadevan-Jansen, and E. Duco Jansen. "Biophysical mechanisms responsible for pulsed low-level laser excitation of neural tissue." In Biomedical Optics 2006, edited by Steven L. Jacques and William P. Roach. SPIE, 2006. http://dx.doi.org/10.1117/12.655239.

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Thumuluru, Sai Kumar, Mohan K. Bobba, and Tim Lieuwen. "Mechanisms of the Nonlinear Response of a Swirl Flame to Harmonic Excitation." In ASME Turbo Expo 2007: Power for Land, Sea, and Air. ASMEDC, 2007. http://dx.doi.org/10.1115/gt2007-27932.

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This paper describes an experimental investigation of the amplitude dependent processes controlling the response of a swirling flame to harmonic excitation. Simultaneous measurements of the acoustic pressure, velocity, and CH* and OH* radical chemiluminescence were obtained over a range of forcing frequencies, amplitudes, and nozzle exit velocities. These were supplemented with OH planar laser induced fluorescence (PLIF) measurements at several representative conditions. The results presented show that there exist substantial nonlinearities in the flame response to forced oscillations. Furthermore, while the flame response monotonically and linearly increases with perturbation amplitude for low forcing levels, its behavior becomes much more complex at higher levels — this includes saturation as well as more complex, non-monotonic behaviors. Analysis of the OH PLIF images show that the observed dynamics result from a superposition of at least five flame/flow processes — (1) the oscillating velocity of the annular jet, oscillations in (2) position and (3) strength of the vortex breakdown bubble and separation bubble, (4) unsteady liftoff of the flame, and (5) an oscillating turbulent flame speed. These processes generally occur simultaneously, with non-monotonic dependencies upon forcing amplitude. This sheds some light on the complex overall flame heat release response measurements and suggests a fruitful area for detailed computational studies that can better elucidate the underlying physics controlling the phenomenon.
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Sarkar, Saugata, Amy Lutkus, James Mahaney, Harry Dorn, Tom Campbell, Dave Geohegan, and Marissa Nichole Rylander. "Carbon Nanohorns as Photochemical and Photothermal Agents." In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206796.

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Laser therapies based on photochemical or photothermal mechanisms can provide a minimally invasive and potentially more effective treatment alternative to conventional surgical resection procedures by delivering prescribed optical/thermal doses to a targeted tissue volume with minimal damage to intervening and surrounding tissues. However laser therapy effectiveness is limited due to nonspecific excitation/heating of target tissue which often results in healthy tissue injury. Nanostructures targeted to tumor cells and utilized in combination with laser excitation can enhance treatment effectiveness by increasing thermal deposition and generating toxic photo-chemical mediators in the form of reactive oxygen species for targeted cell destruction.
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Zhigilei, Leonid V., Zhibin Lin, and Dmitriy S. Ivanov. "Molecular Dynamics Study of Short-Pulse Laser Melting, Recrystallization, Spallation, and Ablation of Metal Targets." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-16305.

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A hybrid computational model combining classical molecular dynamics method for simulation of fast nonequilibrium phase transformations with a continuum description of the laser excitation and subsequent relaxation of the conduction band electrons is developed. The model is applied for a systematic computational investigation of the mechanisms of short pulse laser interaction with bulk metal targets. The material response to laser irradiation is investigated in three regimes corresponding to the melting and resolidification of the surface region of the target, photomechanical spallation of a single or multiple layers/droplets, and ablation driven by the thermodynamic driving forces. The conditions leading to the transitions between the different regimes and the atomic-level characteristics of the involved processes are established.
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O’Donoghue, Declan, Valeria Nico, Ronan Frizzell, Gerard Kelly, and Jeff Punch. "A Multiple-Degree-of-Freedom Velocity-Amplified Vibrational Energy Harvester: Part A — Experimental Analysis." In ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/smasis2014-7510.

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Vibrational energy harvesters (VEHs) are devices which convert ambient vibrational energy into electrical power, offering an alternative to batteries for powering wireless sensors. Detailed experimental characterisation of a 2-degree-of-freedom (2-Dof) VEH is presented in Part A of this paper, while a theoretical analysis is completed in Part B. This design employs velocity amplification to enhance the power harvested from ambient vibrations, while also seeking to increase the bandwidth over which power can be harvested. Velocity amplification is achieved through sequential collisions between free-moving masses. Electromagnetic induction was chosen as the transduction mechanism as it can be readily implemented in a velocity amplified system, although other transduction mechanisms can also be used. The VEH prototype was tested experimentally under both sinusoidal excitation and exponentially correlated Gaussian noise, with different VEH geometries. The maximum power generated under a sinusoidal excitation of arms = 0.6 g was 12.95 mW for a resistive load of 13.5 Ω at 12 Hz, while the maximum power under exponentially correlated Gaussian noise with σ = 0.8 grms, autocorrelation time τ = 0.01s and resistive load 13.5 Ω was 5.3 mW. Maximum bandwidths of 54% and 66%, relative to the central frequency, were achieved under sinusoidal and noise excitation, respectively. The device shows resonant peaks at approximately 15 and 30 Hz, while significant power is also generated in the 17–20 Hz range due to non-linear effects. The VEH component dynamics were analysed using a laser Doppler vibrometer (LDV), while Lab VIEW was used to control the electromagnetic shaker, read the LDV signal and record the VEH output voltage. The aim of this investigation is to achieve a more complete understanding of the dynamics of velocity-amplified systems to aid the optimization of velocity amplified VEH designs.
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