Artigos de revistas: "Pulsed laser system"

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Chen, Fu-Zen, Yu-Cheng Song e Fu-Shun Ho. "An Efficiency Improvement Driver for Master Oscillator Power Amplifier Pulsed Laser Systems". Processes 10, n.º 6 (16 de junho de 2022): 1197. http://dx.doi.org/10.3390/pr10061197.

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The master oscillator power amplifier (MOPA) pulsed laser, one of the popular topologies for high-power fiber laser systems, is widely applied in industrial machining laser systems. In MOPA, the low-power pulsed laser, stimulated from a seed laser diode, is amplified by the high- power optical energy from pump laser diodes via the gain fiber. Generally, the high-power pump laser diodes are driven by lossy linear current drivers. The switched mode current drivers boost the driver efficiency but suffer from pulse energy consistency due to the current switching ripple. In this paper, a laser driver system that varies the switching frequency of current source to synchronize with pulsed laser repetition rate is analyzed and implemented. Experimental results are demonstrated using a 20 W pulsed fiber laser system.

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Ustimchik, V., E. Motorin e V. Filippov. "High peak/average power picosecond pulsed MOPA system with tapered large mode area double-clad Yb-doped fiber". EPJ Web of Conferences 266 (2022): 11014. http://dx.doi.org/10.1051/epjconf/202226611014.

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In this paper, a high peak/average power picosecond pulsed master‑oscillator power‑amplifier (MOPA) system utilizing tapered large mode area double-clad fiber (T-DCF) is presented. In a high average power regime, we report a pulsed MOPA laser system with average power up to 613 W at 20 MHz repetition rate with 50 ps pulse duration (613 kW of peak power and 30.6 μJ pulse energy). In high peak power regime, over 3MW of peak power pulses (at seed source bandwidth) at 1 MHz repetition rate (310 μJ pulse energy and 310 W average) was demonstrated. The outstanding properties of T-DCF for amplification of laser signals to high power/energy levels with maintaining the excellent beam quality open a new horizon for advanced laser material processing.

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SUGIMOTO, Shigeto, Tetsuya KIGUCHI, Michinobu MIZUMURA, Koichi KAJIYAMA e Junji KIDO. "Pulsed Laser System with Variable Pulse Duration for Laser Annealing". Review of Laser Engineering 41, n.º 12 (2013): 1031. http://dx.doi.org/10.2184/lsj.41.12_1031.

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Bostanjoglo, O., F. Heinricht e F. Wünsch. "Performance of A Laser-Pulsed Thermal Electron Gun". Proceedings, annual meeting, Electron Microscopy Society of America 48, n.º 1 (12 de agosto de 1990): 124–25. http://dx.doi.org/10.1017/s0424820100179373.

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High-speed electron microscopy strongly demands a high-brightness electron gun in order to increase the number of image forming electrons. A few years ago, a laser-pulsed high-brightness electron gun was introduced. Fig.1 shows the experimental set-up, A standard triode system was supplemented with a Nd:YAG laser, focussing optics and a modified anode, which incorporates the laser deflection mirror. The frequency doubled laser pulse (τ =5 ns, λ = 532 nm) is focused through a window onto the tip of the tungsten hairpin emitter. The laser treated area (≈ 100 μm diameter) is heated well above the melting point, which results in a strong thermal electron emission. Due to rapid heat-up and fast cool-down of the tungsten surface short electron pulses with a duration of 20 ns and a maximum current of 20 mA at 80 kV are emitted. A destruction of the tungsten wire is avoided, too. Laser energies used for the generation of electron pulses are in the range of 100 μJ. Due to these minor modification, the DC operation of the electron gun is not disabled, which allows a convenient adjustment in the DC mode and then switching into the pulsed operation mode. Fig.2 shows a typical electron pulse emitted by the gun. Shorter electron pulses up to 5 ns can be generated by a beam blanking unit.

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Tikhomirov, S. A. "Femtosecond System with Pulse Pumping of Seed Laser and Amplifier by Using a Single Power Unit". Devices and Methods of Measurements 12, n.º 1 (19 de março de 2021): 23–29. http://dx.doi.org/10.21122/2220-9506-2021-12-1-23-29.

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For several decades development of methods for generating ultrashort pulses has been an independent urgent scientific and technical problem. There is a constant improvement both in the methods of such pulses receiving and in methods of their use. The aim of this work was to investigate the possibility of realizing the coordinated operation of two fundamentally different types of pump lasers for the femtosecond oscillator and amplifier based on one single-lamp laser head and to create on this basis a compact high-power femtosecond system with pulsed pumping and one power unit.The practical implementation of two types of pulsed lasers (nano- and picosecond ones operating, respectively, in Q-switch and modelock regime) on a single laser head with two active elements and one pump lamp is carried out. The required synchronization in time the pump pulse femtosecond amplifier formation and quasi-stationary region of generated pulses in the output radiation of a femtosecond Ti:sapphire is obtained.On this basis a compact, pulse pumped monoblock laser system has been developed that can generate femtosecond pulses with a duration of 50–150 fs with an energy up to 1 mJ and a high enough pulse repetition rate (up to 1 kHz which is determined by the type of laser head and pump unit used). In the developed laser system a compact scheme of a stretcher-compressor with a single common diffraction grating is used.Laser systems of this type characterized by a relatively low cost due to the use of a single power supply unit for simultaneous pumping of the amplifier and oscillator, as well as lower requirements for the quality of optical elements and usage conditions due to the pulse mode of operation, are quite practical and can be used both in scientific research in the field of ultra-high-speed kinetic spectroscopy and nonlinear optics, as well as in numerous technical applications, particular in the precision processing of materials, as optical simulators of the action of heavy charged particles in testing the radiation resistance of integrated circuits and electronic modules.

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Razhev, Aleksandr, Dmitriy Churkin e Alexey Zavyalov. "Pulsed Inductive Molecular Hydrogen Laser". Siberian Journal of Physics 4, n.º 3 (1 de outubro de 2009): 12–19. http://dx.doi.org/10.54362/1818-7919-2009-4-3-12-19.

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A pulsed inductive discharge molecular H2 laser has been created for the first time. The excitation system of a toroidal pulsed inductive discharge for molecular hydrogen electron levels excitation was developed. Generation at two wavelengths of 0,89 and 1,12 m was obtained. The spectral, temporal and energy parameters of laser emission under various pressures and pumping conditions were investigated. The maximum pulse power of 6,7 kW was achieved. The measured pulse duration was 18 ± 1 ns. In the cross-section, the laser radiation had the ring shape with an external diameter of 33 mm and thickness of 4 mm.

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Shemyakin, A. N., M. Yu Rachkov, N. G. Solov’ev e M. Yu Yakimov. "Radiation Power Control of the Industrial CO₂ Laser Excited by а Nonself-Sustained Glow Discharge by Changing the Frequency of Ionization Pulses". Mekhatronika, Avtomatizatsiya, Upravlenie 21, n.º 4 (11 de abril de 2020): 224–31. http://dx.doi.org/10.17587/mau.21.224-231.

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The article describes radiation power control of industrial CO2 lasers of Lantan series excited by а nonself-sustained glow discharge in the automatic mode. These lasers are closed-cycle fast gas-transport lasers excited by a nonself-sustained glow discharge with ionization by periodic-pulsed capacitively coupled auxiliary discharge. In this case, ionization and conductivity are provided by periodic-pulsed capacitively coupled discharge. The energy contribution to molecular oscillations is provided by the passage of the main discharge current through the plasma with electron density given by ionization. This permits easy laser power control, provides excellent optical homogeneity and stability of an active volume together with high laser efficiency. A system of a nonself-sustained glow discharge with ionization by periodic-pulsed capacitively coupled auxiliary discharge, the stages of creation and brief characteristics of the Lantan series lasers is presented. The method of controlling the power of laser radiation by changing the frequency of the ionization pulses is determined. This control method allows operating of the laser in continuous and in pulse-periodic modes with adjustable pulse ratio and pulse duration, and also provides switching from one mode to another. In the continuous mode, the radiation power is controlled by changing the frequency of ionization pulses, which are high voltage pulses with duration of 100 ns, given with the frequency of 1-5 kHz. Pulse-periodic radiation control is performed by modulating ionization pulses that consists of pulses being delivered in batches. The frequency of the pulses in a batch determines the radiation power in a pulse. The frequency of the batches following is the frequency of the pulse mode, and the length of the batch determines the pulses duration. Based on the experimental data, the dependence of the radiation power on the ionization pulses frequency was determined. An experimental system is presented and the measuring accuracy of the laser radiation power and the frequency of ionization pulses is determined. Data acquiring and processing of experimental results were performed using the NI 6008 USB data acquisition device in the LabVIEW programs of National Instruments. To study the dependence of the laser power on Мехатроника, автоматизация, управление, Том 21, № 4, 2020 231 the frequency of the ionization pulses, a regression analysis method was applied. Studies have shown that the dependence of the laser power on the ionization pulses frequency is linear in a wide range of parameters. The equation of the direct regression is calculated. The confidence estimates of the coefficients of the direct regression and the confidence estimates of the deviation of the theoretical direct regression from the empirical one are calculated with a confidence level of 95%.

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Zayhowski, J. J., e A. L. Wilson. "Miniature, pulsed Ti:sapphire laser system". IEEE Journal of Quantum Electronics 38, n.º 11 (novembro de 2002): 1449–54. http://dx.doi.org/10.1109/jqe.2002.804294.

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Lowry, J. B., W. T. Welford e M. R. Humphries. "Pulsed Scophony laser projection system". Optics & Laser Technology 20, n.º 5 (outubro de 1988): 255–58. http://dx.doi.org/10.1016/0030-3992(88)90027-8.

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Zhan, Wei, e He Hua Ju. "Offset Error Research of Self-Triggering Pulsed Mini Laser Radar System". Applied Mechanics and Materials 599-601 (agosto de 2014): 1009–15. http://dx.doi.org/10.4028/www.scientific.net/amm.599-601.1009.

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The paper researches on the offset error of self-triggering pulsed mini laser radar. It theoretically analyzes the variation of space charge region of PN junction in receiving photodiode. The variation value is affected by the different incident light power. One of conclusion is the laser pulse time-of-flight affected by the variation of incident light power. Another conclusion is the laser pulse width affected by the variation of incident light power as well. The paper proposes the basic equations to describe this phenomenon. In addition, the new designed experimental devices are used to prove that the theoretical analysis is true. This new system can effectively solve the offset error problems, and the negatively impact of offset error will be eliminated on the receiver of self-triggering pulsed mini laser radar system.

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Angel, G., R. Gagel e A. Laubereau. "Generation of femotsecond pulses by a pulsed laser system". Optics Communications 63, n.º 4 (agosto de 1987): 259–63. http://dx.doi.org/10.1016/0030-4018(87)90351-8.

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Kavaya, Michael J., Jeffrey Y. Beyon, Grady J. Koch, Mulugeta Petros, Paul J. Petzar, Upendra N. Singh, Bo C. Trieu e Jirong Yu. "The Doppler Aerosol Wind (DAWN) Airborne, Wind-Profiling Coherent-Detection Lidar System: Overview and Preliminary Flight Results". Journal of Atmospheric and Oceanic Technology 31, n.º 4 (1 de abril de 2014): 826–42. http://dx.doi.org/10.1175/jtech-d-12-00274.1.

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Abstract The first airborne wind measurements of a pulsed, 2-μm solid-state, high-energy, wind-profiling lidar system for airborne measurements are presented. The laser pulse energy is the highest to date in an eye-safe airborne wind lidar system. This energy, the 10-Hz laser pulse rate, the 15-cm receiver diameter, and dual-balanced coherent detection together have the potential to provide much-improved lidar sensitivity to low aerosol backscatter levels compared to earlier airborne-pulsed coherent lidar wind systems. Problems with a laser-burned telescope secondary mirror prevented a full demonstration of the lidar’s capability, but the hardware, algorithms, and software were nevertheless all validated. A lidar description, relevant theory, and preliminary results of flight measurements are presented.

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Golovkov, V. A., N. I. Potapova, P. N. Rudenko, B. G. Stradov e S. V. Teliatnikov. "Receiving Unit of a Precision Pulsed Laser Range Finder". Journal of the Russian Universities. Radioelectronics 23, n.º 2 (28 de abril de 2020): 73–81. http://dx.doi.org/10.32603/1993-8985-2020-23-2-73-81.

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Introduction. At present the most accurate estimate of ranges is specific to laser range finders using phase measuring techniques. Design of a pulsed laser range finder with short probe pulses enabling one to gain high resolution and accuracy of estimate of target range close to the phase range finders is the topical problem.Aim. Development of a receiving part of the pulsed laser rangefinder with precision characteristics; determination of the accuracy of the measurements; description of the hardware.Materials and methods. The construction of the receiving part of the precision pulsed laser rangefinder with a two-scale digital range estimation system implemented by counting clock generator pulses and an analog integrator that specifies the discrete range estimation was considered. Using the methods of mathematical statistics, the energy characteristics of the rangefinder were determined: the accuracy of the range estimation and the probability of false alarm were provided by the developed scheme. The hardware of the precision laser rangefinder was described.Results. The principles of implementation of the receiving part of the laser rangefinder with a two-scale digital system for estimating the distance to the object were given. The results of numerical simulation of rangefinder characteristics were obtained, confirming the accuracy of range estimation of the order of millimeters. In the implemented rangefinder scheme, the probability of false alarm was 10-4 during 200 s of observing signal and noise mixture. The hardware of the precision laser rangefinder with a digital two-scale range estimation was proposed.Conclusion. The implemented laser range finder approaches to the capabilities of phase laser rangefinders in terms of potential accuracy of distance up to millimeters, while implementing the specified parameter in rapidly changing phono-target environment. Using of short probing pulses with a duration of 10...20 ns allows one to achieve a resolution of up to 1.5 m. In contrast to the phase rangefinder the range can be estimated from a single probe pulse.

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Kotula, Paul G., e C. Barry Carter. "Characterization of NiO thin films on α-Al2O3 before and after heat treatment". Proceedings, annual meeting, Electron Microscopy Society of America 51 (1 de agosto de 1993): 1120–21. http://dx.doi.org/10.1017/s042482010015143x.

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The NiO-α-Al2O3 system is of interest as a model system for the study of phase boundaries and reaction kinetics in oxide ceramics. Such a system is of new importance when one of the constituents is a thin film because the reaction kinetics and its dependence on film microstructure is not well understood. Additionally, solid-state reactions between a thin film and single-crystal substrate can be used to produce buffer layers for heterojunctions.In the present study, thin films of NiO have been grown on single-crystal α-Al2O3 substrates by pulsed-laser ablation (PLA). The PLA system used a KrF (248nm) excimer laser operating at 350 mJ per pulse with a pulse repetition rate of 10 Hz. The laser beam was focused to a spot 1×2mm on the surface of rotating NiO pellet. Films were grown at nominal substrate temperatures of 750°C and oxygen pressures of about 10 mTorr. Films were grown both on bulk substrates for which 6000 laser pulses was used to produce 1000Å films and electron-transparent substrates for which 500 laser pulses was used to produce 80Å films.

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Zhao, Lu, Antoine Normand, Jonathan Houard, Ivan Blum, Fabien Delaroche, Olivier Latry, Blaise Ravelo e Francois Vurpillot. "Optimizing Atom Probe Analysis with Synchronous Laser Pulsing and Voltage Pulsing". Microscopy and Microanalysis 23, n.º 2 (8 de fevereiro de 2017): 221–26. http://dx.doi.org/10.1017/s1431927616012666.

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AbstractAtom probe has been developed for investigating materials at the atomic scale and in three dimensions by using either high-voltage (HV) pulses or laser pulses to trigger the field evaporation of surface atoms. In this paper, we propose an atom probe setup with pulsed evaporation achieved by simultaneous application of both methods. This provides a simple way to improve mass resolution without degrading the intrinsic spatial resolution of the instrument. The basic principle of this setup is the combination of both modes, but with a precise control of the delay (at a femtosecond timescale) between voltage and laser pulses. A home-made voltage pulse generator and an air-to-vacuum transmission system are discussed. The shape of the HV pulse presented at the sample apex is experimentally measured. Optimizing the delay between the voltage and the laser pulse improves the mass spectrum quality.

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Fotiou, Fotios K., e Michael D. Morris. "Photothermal Deflection Densitometer with Pulsed-UV Laser Excitation". Applied Spectroscopy 40, n.º 5 (julho de 1986): 700–704. http://dx.doi.org/10.1366/0003702864508610.

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First application of pulsed photothermal deflection spectroscopy to solid samples is demonstrated. A new densitometer for thin layer chromatography based on this method is described. The technique is suitable for direct measurements in the ultraviolet region. A pulsed excimer laser is used to produce a transient thermal refractive index gradient. The laser delivers pulses of 1–2 mJ at 10–22 pulses/s, at 351 nm. With this system the detection limit for 2,4-dinitroaniline is 750 pg. The signal is linear with amount of analyte for about three orders of magnitude.

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Wang, Jing Xuan, Lan Tian, Chen Li, Dong Yu Lu e Nan Yang. "Applied Technology in Evoked Auditory Response In Vivo Animal Cochlea by 980nm Pulsed Laser Light". Advanced Materials Research 886 (janeiro de 2014): 355–58. http://dx.doi.org/10.4028/www.scientific.net/amr.886.355.

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Optical cochlear implant is an emerging applied technology of stimulating auditory neurons by using pulsed laser light as a stimulus to evoke neural activity instead of electrical currents. Laser stimulation has more potential in accuracy and high frequency resolution than electrical stimulation. In this paper we demonstrated a fiber laser system (980nm) to irradiate on guinea pig cochlear in vivo for the first time. The pulsed laser stimulation successfully evoked auditory nervous impulse, similar to acoustic stimulation. And the performance under different laser pulse intensity and pulse width is further tested and discussed. The results show that the 980nm pulsed laser stimulation with microsecond level width is effective and safe to evoke auditory response. Photoacoustic or photothermal effects maybe the main mechanism. In the end, we put forward some prospects of the applied technology in cochlear implant.

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Mikhaylyuk A. V., Gubskiy K. L., Kazieva T. V. e Kuznetsov A. P. "Stabilization of a single-frequency generation of the injection-seeded pulsed solid-state laser". Technical Physics Letters 48, n.º 6 (2022): 19. http://dx.doi.org/10.21883/tpl.2022.06.53458.19168.

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The article presents the results of developing the single-frequency pulsed Nd : YAG laser system at the 660 nm wavelength with a pulse duration of 50 ns and repetition rate of 1-10 Hz, operating in a Q-switched mode with injection of external radiation. Various schemes of forming a feedback system for controlling the spectral composition of the laser system are considered. It is shown that the method of locking the master oscillator frequency to the mode of the pulsed laser cavity has a number of advantages over the method of stabilizing the cavity length. Keywords: Solid-state laser, Q-switching modulation, injection of radiation.

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Venkatakrishnan, Krishnan. "Femtosecond pulsed laser direct writing system". Optical Engineering 41, n.º 6 (1 de junho de 2002): 1441. http://dx.doi.org/10.1117/1.1476324.

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Sadchenko, A. V., O. A. Kushnirenko e E. K. Koshelev. "Anti-interference pulsed laser ranging system". Технология и конструирование в электронной аппаратуре, n.º 1-2 (2020): 8–14. http://dx.doi.org/10.15222/tkea2020.1-2.08.

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Pulsed laser rangefinders prove to be cost-effective and practical devices when used at distances of several tens of kilometers due to their compactness, portability and energy efficiency. However, the measurement accuracy is significantly reduced by the presence of pulsed interference affecting the input of the optical receiver both during the sensing period and when the reflected signal is being received. Using the algorithms with the accumulation and subsequent processing of the results of several successive measurements reduces the speed of decision-making and does not guarantee the convergence of the results to the real value of the distance. The paper proposes a structural diagram of a laser rangefinder with the ability to detect pulsed interference in the range interval and correct errors that occur in the structure of the signal reflected from the target. The basis of the rangefinder circuit is a logical consistent filter, the structure of which contains multipliers (multiplication operations). The following requirements were formulated for the structure of the probe signal: — the first element should always be set to +1 to synchronize the receiver decider; — the weight of the coding sequence is equal to half its length; — the length of the coding sequence is even. Based on the requirements for coding sequences, the optimal structures of binary probing signals of length 8 were found, providing the best corrective ability. Comparison of the correlation properties of the found sequences and the sequences that are constructed using the Walsh functions showed the advantage of the optimal sequences by the criterion of the minimum level of the ACF side lobes. The simulation of the rangefinder under pulsed noise conditions has shown that the logical filter is advisable to use for those cases when the duration of the obstacle does not exceed 1/3 of the duration of the probing signal.

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Lavrent’ev, K. K. "Repetitively Pulsed Solid-State Laser System with SBS Pulse Compression". Optics and Spectroscopy 89, n.º 1 (julho de 2000): 150. http://dx.doi.org/10.1134/1.1131532.

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Lavrent’ev, K. K., R. L. Sabirov, S. A. Chizhov e V. E. Yashin. "Repetitively pulsed solid-state laser system with SBS pulse compression". Optics and Spectroscopy 89, n.º 1 (julho de 2000): 150–54. http://dx.doi.org/10.1134/bf03356006.

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Tereszchuk, K. A., J. M. Vadillo e J. J. Laserna. "Glow-Discharge-Assisted Laser-Induced Breakdown Spectroscopy: Increased Sensitivity in Solid Analysis". Applied Spectroscopy 62, n.º 11 (novembro de 2008): 1262–67. http://dx.doi.org/10.1366/000370208786401491.

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A glow discharge operating in steady-state and pulsed temporal conditions is used to excite the material previously excited by a pulsed laser ablation system. The system provides a simple means by which to potentially excite the material ablated by the incident laser pulse by taking advantage of enhanced collisional excitation. In this way, one can effectively reduce laser pulse energies below the excitation and ionization thresholds to potentially those required solely for laser ablation of the material, reducing sample damage and improving the lateral resolution. Several critical parameters such as the gas pressure, gas type, and discharge voltage were evaluated, demonstrating the potential of the technique for spatially resolved analysis. The new dual glow-discharge laser-induced breakdown spectroscopy (GD-LIBS) synchronous scheme provides significant signal enhancements when compared to LIBS or GD under identical conditions.

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Alekseev, V. A., M. R. Zaripov, A. S. Perminov, E. A. Sitnikova, V. P. Usol’tsev e S. I. Yuran. "Increasing of Pulsed Laser Source Peak Power by Use of Ring Fiber-Optic Delay Line". Devices and Methods of Measurements 10, n.º 2 (24 de junho de 2019): 151–59. http://dx.doi.org/10.21122/2220-9506-2019-10-2-151-159.

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At the present time, developing of autonomous laser systems requires increasing of the output power of the laser sources used in composition of those systems and at the same time reducing of the energy usage in the system. The possibility of increasing output peak power of pulsed laser sources by using the method of synchronous non-coherent beam combining in ring fiber-optic delay line is considered by authors. Objective of this work was estimating energy effectiveness of laser systems, which based on this method.General constructing method of the laser pulsed laser source with ring fiber delay line is considered, its block diagram and the general operating principle of similar systems are presented. Two versions of laser systems based on the described method of beam combining are presented: using an optical combiner and an optical switch; using fiber welding instead of a combiner and an optical switch. The graphical dependence of the energy effectiveness on the number of circulations in ring fiber-optic delay line is obtained for both versions of laser systems.As a result of the analysis of the considered devices operation, it was shown that considered systems allow to obtain increasing the peak power of a laser pulse without increasing the power supply, also the system, that use welded fi instead of the optical combiner, has greater effi than system with optical combiner.

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Dzyubenko, M., I. Kolenov, V. Pelipenko, N. Dakhov e A. Degtyarev. "Laser rangefinder of relatively eye-safe wavelength range". RADIOFIZIKA I ELEKTRONIKA 26, n.º 1 (2021): 41–48. http://dx.doi.org/10.15407/rej2021.01.041.

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Subject and Purpose. The development and prototype making of a laser rangefinder operating in the 1.50…1.70 μm spectral region is reported. This wavelength region is attractive to both laser producers and laser users for, first of all, relative eye-safety of radiation. Methods and Methodology. The paraxial scheme of rangefinder construction is used, involving a software-controlled power supply of laser radiation with technical arrangements providing its adaptation to varying operating conditions. The alignment of the transceiver channels is provided with laser beam visualization methods. Results. A pulsed laser rangefinder operating at a 1.54 μm wavelength has been developed, a prototype has been made. The rangefinder essentially consists of the transmitting and receiving channels and the visual channel for targeting. The radiation source is a pulsed laser on ytterbium-erbium glass with semiconductor diode pumping and modulated Q-factor. The laser provides a 6 mJ power pulse of 25 ns duration and 5 mrad radiation divergence. A laser light spot of a required aperture is formed using a Galilean telescope system. For the photodetector of the reflected radiation, a pin-photodiode with a photosensitive area diagonal of 0.3 mm and a 2.5 ns time resolution is used. The echo signal processing module has been developed and performed, providing a high-precision registration of a time delay between the starting and reflected pulses. An effective method with the use of a charge-coupled device and an LCD monitor has been proposed and implemented for the alignment of all the three rangefinder channels. The rangefinder can operate in a single-pulse or repetitive-pulse mode with a probing pulse repetition rate of 1 Hz. Conclusion. A pulsed laser rangefinder operating in a relatively eye-safe spectrum region has been developed, a prototype has been made. The field tests have shown that the created rangefinder measures an object distance within 140…7 000 m with a measurement error no worse than 3 m.

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Hiroi, Takashi, Sadaki Samitsu, Hideaki Kano e Kunie Ishioka. "Calibration for a count rate-dependent time correlation function and a random noise reduction in pulsed dynamic light scattering". Analytical Sciences 38, n.º 3 (15 de fevereiro de 2022): 607–11. http://dx.doi.org/10.1007/s44211-022-00071-0.

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AbstractA pulsed dynamic light scattering (DLS) system, which would be potentially applied to nonlinear DLS with molecular selectivity, was developed by combining a sub-nanosecond pulsed laser with a software-based detection system. The distortion of the time correlation function due to the clipping effect in the photon counting module, and the resulting underestimation of the particle size, were successfully calibrated based on a theoretical simulation. The effective removal of random noises was also demonstrated via time gating synchronized to the laser pulses. Graphical abstract

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Tomov, I. V., P. Chen e P. M. Rentzepis. "Picosecond X-ray Diffraction: System and Applications". Advances in X-ray Analysis 38 (1994): 21–33. http://dx.doi.org/10.1154/s0376030800017614.

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Abstract We report the development of a novel, pulsed x-ray diffraction system with picosecond time resolution. The system has been used to study the heat transport in gold, platinum and silicon crystals heated by 10 ps, 193 nm laser pulses. Further developments and applications of time resolved picosecond x-ray diffraction are discussed.

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Meyer, Kristina, Zuoye Liu, Niklas Müller, Jan-Michael Mewes, Andreas Dreuw, Tiago Buckup, Marcus Motzkus e Thomas Pfeifer. "Signatures and control of strong-field dynamics in a complex system". Proceedings of the National Academy of Sciences 112, n.º 51 (8 de dezembro de 2015): 15613–18. http://dx.doi.org/10.1073/pnas.1509201112.

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Controlling chemical reactions by light, i.e., the selective making and breaking of chemical bonds in a desired way with strong-field lasers, is a long-held dream in science. An essential step toward achieving this goal is to understand the interactions of atomic and molecular systems with intense laser light. The main focus of experiments that were performed thus far was on quantum-state population changes. Phase-shaped laser pulses were used to control the population of final states, also, by making use of quantum interference of different pathways. However, the quantum-mechanical phase of these final states, governing the system’s response and thus the subsequent temporal evolution and dynamics of the system, was not systematically analyzed. Here, we demonstrate a generalized phase-control concept for complex systems in the liquid phase. In this scheme, the intensity of a control laser pulse acts as a control knob to manipulate the quantum-mechanical phase evolution of excited states. This control manifests itself in the phase of the molecule’s dipole response accessible via its absorption spectrum. As reported here, the shape of a broad molecular absorption band is significantly modified for laser pulse intensities ranging from the weak perturbative to the strong-field regime. This generalized phase-control concept provides a powerful tool to interpret and understand the strong-field dynamics and control of large molecules in external pulsed laser fields.

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Xiong, Wei, Qingsong Bai, Yuqi Hu, Xing Zhang, Yilu Wu, Guangqiong Xia, Heng Zhou, Jiagui Wu e Zhengmao Wu. "3D parallel pulsed chaos LiDAR system". Optics Express 32, n.º 7 (15 de março de 2024): 11763. http://dx.doi.org/10.1364/oe.515059.

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We propose and experimentally demonstrate a parallel pulsed chaos light detection and ranging (LiDAR) system with a high peak power, parallelism, and anti-interference. The system generates chaotic microcombs based on a chip-scale Si3N4 microresonator. After passing through an acousto-optic modulator, the continuous-wave chaotic microcomb can be transformed into a pulsed chaotic microcomb, in which each comb line provides pulsed chaos. Thus, a parallel pulsed chaos signal is generated. Using the parallel pulsed chaos as the transmission signal of LiDAR, we successfully realize a 4-m three-dimensional imaging experiment using a microelectromechanical mirror for laser scanning. The experimental results indicate that the parallel pulsed chaos LiDAR can detect twice as many pixels as direct detection continuous wave parallel chaos LiDAR under a transmission power of -6 dBm, a duty cycle of 25%, and a pulse repetition frequency of 100 kHz. By further increasing the transmission power to 10 dBm, we acquire an 11 cm × 10 cm image of a target scene with a resolution of 30 × 50 pixels. Finally, the anti-jamming ability of the system is evaluated, and the results show that the system can withstand interferences of at least 15 dB.

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Lorusso, Antonella, László Égerházi, Sándor Szatmári e Tamás Szörényi. "The Potential of Spot Size Control in Shaping the Thickness Distribution in Ultrashort Laser Deposition". Materials 17, n.º 11 (3 de junho de 2024): 2712. http://dx.doi.org/10.3390/ma17112712.

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The availability of new-generation femtosecond lasers capable of delivering pulses with energies in the hundreds of mJ, or even in the joules range, has called for a revision of the effect of scaling spot size on the material distribution within the plasma plume. Employing a state-of-the-art Szatmári-type hybrid dye-excimer laser system emitting 248 nm pulses with a maximum energy of 20 mJ and duration of 600 fs, copper films were grown in the classical pulsed laser deposition geometry. The exceptionally clean temporal profile of the laser pulses yielded a femtosecond component of 4.18 ± 0.19 mJ, accompanied by a 0.22 ± 0.01 mJ ASE pedestal on the target surface. While varying the spot sizes, the plasma plume consistently exhibited an extremely forward-peaked distribution. Deposition rates, defined as peak thickness per number of pulses, ranged from 0.030 to 0.114 nm/pulse, with a gradual narrowing of the thickness distribution as the spot area increased from 0.085 to 1.01 mm2 while keeping the pulse energy constant. The material distribution on the silicon substrates was characterized using the f(Θ) = AcoskΘ + (1 − A)cospΘ formalism, revealing exponents characterizing the forward-peaked component of the thickness profile of the film material along the axes, ranging from k = 15 up to exceptionally high values exceeding 50, as the spot area increased. Consequently, spot size control and outstanding beam quality ensured that majority of the ablated material was confined to the central region of the plume, indicating the potential of PLD (pulsed laser deposition) for highly efficient localized deposition of exotic materials.

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Sonnenschein, Volker, e Hideki Tomita. "A Hybrid Self-Seeded Ti:sapphire Laser with a Pumping Scheme Based on Spectral Beam Combination of Continuous Wave Diode and Pulsed DPSS Lasers". Applied Sciences 12, n.º 9 (7 de maio de 2022): 4727. http://dx.doi.org/10.3390/app12094727.

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A wide variety of applications require high peak laser intensity in conjunction with a narrow spectral linewidth. Typically, injection-locked amplifiers have been employed for this purpose, where a continuous wave oscillator is amplified in a secondary external resonant amplifier cavity using a pulsed pump laser. In contrast, here we demonstrate a setup that combines a CW Ti:sapphire oscillator and pulsed amplifier in a single optical cavity, resulting in a compact system. Dichroic beam combination of blue wavelength semiconductor diodes and the green wavelength of a Nd:YAG laser allowed the simultaneous excitation of the Ti:sapphire crystal by both continuous wave and pulsed pump sources. A linewidth of <2 MHz is achieved in continuous wave operation, while the linewidth increases to about 10 MHz in the combined CW+pulsed mode with a pulse duration of 73 ns. A peak pulse intensity of 0.2 kW is achieved, which should enable efficient single-pass second harmonic generation in a nonlinear crystal.

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Gubarev, Fedor A. "Multifunctional imaging system based on a laser and a brightness amplifier on copper bromide vapors". Proceedings of Tomsk State University of Control Systems and Radioelectronics 26, n.º 2 (2023): 21–27. http://dx.doi.org/10.21293/1818-0442-2023-26-2-21-27.

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A multifunctional system meant to image the surface of energetic materials during combustion based on copper bromide vapor gain media is proposed. The system allows quickly implement various methods of active visualization and is based on a high-speed video camera, an illuminating laser, and a copper bromide vapor brightness amplifier. Depending on imaging needs, the main components of the system can be configured as a laser-illuminating system, a single-channel laser monitor, or a laser monitor with synchronous laser illumination. A high-voltage pulsed power supply allows connecting both one laser tube and two at the same time, while switching operating modes can be carried out on- the-fly. The source generates one or two synchronized sequences of high-voltage pulses for pumping gasdischarge tubes with a voltage of up to 6 kV and a frequency of 20 kHz. Due to the use of gas discharge tubes with independent control of temperature parameters, the operating modes with a pump power of 500–700 W for each channel can be realized. To generate pump pulses for laser media, a two-channel thyratron circuit for the direct discharge of storage capacitors were used, charged by a common stabilized voltage source provided by a step-down pulse stabilizer and a pulse shaper for charging storage capacitors based on a bridge inverter. A transistor modulator with adjustable delay lines carries out synchronization of the laser illumination and the brightness amplifier in the mode with synchronous laser illumination with an accuracy of ±1 ns.The experimental data of the system operation in various modes are presented. The imaging results for the surface of mixtures of metal nanopowders during combustion, obtained with various configurations of the laser system, are presented.

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Angel, G., R. Gagel e A. Laubereau. "Generation of intense 25-fsec pulses by a pulsed laser system". Optics Letters 14, n.º 18 (15 de setembro de 1989): 1005. http://dx.doi.org/10.1364/ol.14.001005.

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Metzner, Daniel, Markus Olbrich, Peter Lickschat, Alexander Horn e Steffen Weißmantel. "Experimental and Theoretical Determination of the Effective Penetration Depth of Ultrafast Laser Radiation in Stainless Steel". Lasers in Manufacturing and Materials Processing 7, n.º 4 (14 de outubro de 2020): 478–95. http://dx.doi.org/10.1007/s40516-020-00129-9.

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AbstractThis study intends to present a simple two-temperature model (TTM) for the fast calculation of the ablation depth as well as the corresponding effective penetration depth for stainless steel by considering temperature-dependent material parameters. The model is validated by a comparison of the calculated to the experimentally determined ablation depth and the corresponding effective penetration depth in dependence on the pulse duration (200 fs up to 10 ps) and the fluence. The TTM enables to consider the interaction of pulsed laser radiation with the electron system and the subsequent interaction of the electrons with the phonon system. The theoretical results fit very well to the experimental results and enable the understanding of the dependence of the ablation depth and of the effective penetration depth on the pulse duration. Laser radiation with a pulse duration in the femtosecond regime results in larger ablation depths compared to longer-pulsed laser radiation in the picosecond regime. Analogously to the ablation depth, larger effective penetration depths are observed due to considerably higher electron temperatures for laser radiation with pulse durations in the femtosecond regime.

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Louh, Rong-Fuh, e Relva C. Buchanan. "Hole pattern formation in unfired ceramic sheets by pulsed Nd:YAG laser". Journal of Materials Research 5, n.º 4 (abril de 1990): 841–46. http://dx.doi.org/10.1557/jmr.1990.0841.

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Single shot pulses from a Nd:YAG laser have been used to generate different sized holes and patterns in unfired ceramic sheets for electronic packaging applications. The single shot laser pulses were targeted using a computer controlled deflection system and a programmed pattern. With changes in pulse energy level and profile, the laser beam was also used to sinter line patterns in deposited thin and thick films. The surface radial temperature profile resulting from the laser pulse interaction was also directly mapped using a lacquer thermocoat. Effects of the laser pulse energy and beam spot size on laser/ceramic interactions, morphology, and structure of the drilled holes before and after sintering were examined by SEM. High quality hole patterns (of ∼100 μm hole size) were produced in unfired 100 μm thick ceramic sheets up to 100 μm thick using single shot of laser irradiation with 8 mJ pulse energy and 18 nsec pulse duration.

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Yang, Nan, Jing Xuan Wang, Lan Tian e Yong Wang. "Laser Stimulation Control System Design of the Auditory Nerve". Advanced Materials Research 1046 (outubro de 2014): 116–20. http://dx.doi.org/10.4028/www.scientific.net/amr.1046.116.

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Optical stimulation of the inner ear, the cochlea, has been proved as a possible alternative to conventional cochlear implant with the hypothetical improvement of dynamic range and frequency resolution. Moreover, the laser has good directionality character and optical signal between adjacent fibers do not readily interfere. Therefore, cochlear implant based on optical stimulation is promising for further exploration and development. The design of an experimental system for optical stimulation of the cochlea is introduced in this paper. For the important part, the selection of NIR laser and the optical signal control methods were discussed. The pulsed laser light was coupled by fiber or fiber array and radiated to the cochlea. For each channel laser pulse, the width modulation was varied from 10us to 1ms, the pulse repetition rate from 5 Hz to 10 KHz, single pulse energy from 0 to 3.6mJ. The application of high precision DAC made the resolution of the pulse energy regulation up to 1uJ/div. The experiment results show that this design and implementation can meet the requirements on further optical stimulation of the cochlea research.

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Peng, Zirong, Pyuck-Pa Choi, Baptiste Gault e Dierk Raabe. "Evaluation of Analysis Conditions for Laser-Pulsed Atom Probe Tomography: Example of Cemented Tungsten Carbide". Microscopy and Microanalysis 23, n.º 2 (17 de janeiro de 2017): 431–42. http://dx.doi.org/10.1017/s1431927616012654.

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AbstractCemented tungsten carbide has been analyzed using laser-pulsed atom probe tomography (APT). The influence of experimental parameters, including laser pulse energy, pulse repetition rate, and specimen base temperature, on the acquired data were evaluated from different aspects, such as mass spectrum, chemical composition, noise-to-signal ratio, and multiple events. Within all the applied analysis conditions, only 1 MHz pulse repetition rate led to a strong detector saturation effect, resulting in a largely biased chemical composition. A comparative study of the laser energy settings showed that an ~12 times higher energy was required for the less focused green laser of the LEAPTM 3000X HR system to achieve a similar evaporation field as the finer spot ultraviolet laser of the LEAPTM 5000 XS system.

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Golovkov, V. A., N. I. Potapova, P. N. Rudenko e B. G. Stradov. "Receiving system of a pulsed laser rangefinder". Journal of Optical Technology 87, n.º 11 (1 de novembro de 2020): 688. http://dx.doi.org/10.1364/jot.87.000688.

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Burns, Hoyt N. "System design of a pulsed laser rangefinder". Optical Engineering 30, n.º 3 (1991): 323. http://dx.doi.org/10.1117/12.55801.

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Dixon, Timothy H., Thomas J. Pivirotto, Robert F. Chapman e Robert C. Tyce. "A Range-Gated Laser System for Ocean Floor Imaging". Marine Technology Society Journal 40, n.º 2 (1 de maio de 2006): 126–33. http://dx.doi.org/10.4031/002533206787353556.

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We describe tank studies which show that a copper chloride laser is a good illumination source for a deep ocean imaging system. The laser is naturally pulsed (∼20 ns pulse width) at repetition rates of 10 to 20 kHz, and operates with high (1%) efficiency in the blue-green window for optimum transmission in water. A range-gated, scanning imaging system based on this laser can operate with input power of a few hundred watts, obtaining 100m wide digital image coverage of the sea floor from altitudes of 50 m. Measurements of range (bathymetry) and particulate matter distribution within the water column are also possible.

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Carrion, Lionel, Alain Blouin, Christian Padioleau, Paul Bouchard e Jean-Pierre Monchalin. "Single-frequency pulsed laser oscillator and system for laser-ultrasonics". Measurement Science and Technology 15, n.º 9 (18 de agosto de 2004): 1939–46. http://dx.doi.org/10.1088/0957-0233/15/9/035.

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Chen, Ming-Fei, Wen-Tse Hsiao, Wei-Lun Huang, Chun-Wei Hu e Yu-Pin Chen. "Laser coding on the eggshell using pulsed-laser marking system". Journal of Materials Processing Technology 209, n.º 2 (janeiro de 2009): 737–44. http://dx.doi.org/10.1016/j.jmatprotec.2008.02.075.

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Yuan, Wei, Ze Liu, Pengfei Zhao e Jiwei Huo. "A new pulse electromagnet structure to model a transverse magnetic field to pick up the out-of-plane for laser-EMAT integrated system". AIP Advances 12, n.º 9 (1 de setembro de 2022): 095009. http://dx.doi.org/10.1063/5.0107190.

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In order for an electromagnetic acoustic transducer (EMAT) to be able to pick up the out-of-plane vibrations of ultrasonic waves generated by the laser and to facilitate the movement of the system, a new pulse electromagnet EMAT is proposed, which can be combined with a laser to form a new laser–pulse electromagnet EMAT integrated system. Because of the unique structure of the pulse electromagnet EMAT, it can not only generate a uniform transverse magnetic field in the shallow surface of the specimen just below the EMAT receiving coil but also leave enough space above the magnetic field to ensure the smooth radiation of the laser source on the specimen. The optimal parameters of the probe are determined by combining the finite element simulation model and the orthogonal analysis method. The simulation and experimental results show that the pulsed electromagnet can generate at least 0.22 T transverse magnetic field in the specimen when each coil of C-electromagnet, respectively, injects 20 A. The pulsed electromagnet combined with the EMAT coil is used to receive various modes of ultrasonic vibration velocity with the out-of-plane component. It lays a foundation for the research on the simultaneous detection of railhead surface and internal defects by using the new laser–pulse electromagnet EMAT integrated system through one scan.

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Ajmal, Rizwan, Shakeela Bibi, Rizwan Ahmed, M. Sohail, H. Asghar, Z. A. Umar, N. Shahzad e M. A. Baig. "The role of saturable absorbers thickness in the Q-switching of the erbium-doped fiber laser". Laser Physics Letters 20, n.º 3 (27 de janeiro de 2023): 035101. http://dx.doi.org/10.1088/1612-202x/acb3c8.

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Abstract A passively Q-switched Erbium (Er3+) doped fiber laser (EDFL) based on a ZnO saturable absorber (SA) prepared using a pulsed laser deposition (PLD) technique is demonstrated. The in-situ monitoring of the thickness in the PLD system enabled the control of the SA’s thickness during the growth. The thickness of the SA was varied and the output characteristics of the fiber laser with all thicknesses are compared. This study reveals that the performance and efficiency of an EDFL including pulse repetition rates, pulse duration, pulse energy, peak power, stability, and signal-to-noise ratio can be improved by varying the thickness of the SA. Based on the thickness of the SA, the optimized results are also presented. These findings suggest that the thickness control of the SA film grown directly on the fiber ferrule facilitates much-improved EDFL that has potential applications in pulsed laser sources.

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Xu, Dong, Yao Yao, Xing Fu e Chao Wang. "Design of Micromachining System Based on Nanosecond Pulsed Laser". Key Engineering Materials 645-646 (maio de 2015): 1049–53. http://dx.doi.org/10.4028/www.scientific.net/kem.645-646.1049.

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In recent years, pulsed laser processing technology is widely used in MEMS device manufacturing, aerospace technology, precision instrument manufacturing and circuit board processing. According to the characteristics of nanosecond laser, this paper designs a novel nanosecond pulsed laser micromachining system with PMAC card as its core unit. The system can achieve automation control of laser parameters and movement pattern of motion system by software, which can easily realize automatic processing of point, line, and plane structure in micron scale. In this paper, several groups of experiments are taken to test the reliability and accuracy of the machining system and find the group to obtain the best processing result.

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DESAI, T., D. BATANI, A. BERNARDINELLO, G. POLETTI, F. ORSINI, J. ULLSCHMIED, L. JUHA et al. "X-ray microscopy of living multicellular organisms with the Prague Asterix Iodine Laser System". Laser and Particle Beams 21, n.º 4 (outubro de 2003): 511–16. http://dx.doi.org/10.1017/s0263034603214051.

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Soft X-ray contact microscopy (SXCM) experiments have been performed using the Prague Asterix Iodine Laser System (PALS). Laser wavelength and pulse duration were λ = 1.314 μm and τ (FWHM) = 450 ps, respectively. Pulsed X rays were generated using teflon, gold, and molybdenum targets with laser intensities I ≥ 1014 W/cm2. Experiments have been performed on the nematodes Caenorhabditis elegans. Images were recorded on PMMA photo resists and analyzed using an atomic force microscope operating in contact mode. Our preliminary results indicate the suitability of the SXCM for multicellular specimens.

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Lou, Li Yan, Huan Li, Xu You Wang, Wei Wang e Ying Gao. "Effect of Laser Beam on Double Wire Pulsed MIG Welding Process". Applied Mechanics and Materials 130-134 (outubro de 2011): 4169–73. http://dx.doi.org/10.4028/www.scientific.net/amm.130-134.4169.

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Based on the coupling of laser beam and double arcs, a novel process was investigated. This research set up the laser-double wire pulsed MIG hybrid welding system. Meanwhile the current and voltage sensors were used to detect welding current and arc voltage wave-form and high-speed videography system was used to observe the metal transfer process and arc behavior. The three signals were acquired synchronously. The results showed that the synergic action of the three different heat sources leads to a change in metal transfer mode. It was revealed that the metal transfer mode was two droplets per pulse in laser-double wire hybrid welding process while one droplet per pulse in double wire welding process with the same certain experiment parameters. And we also discovered that the arcs were attracted strongly by the laser beam.

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Sakamoto, Akira, Hiromi Okamoto e Mitsuo Tasumi. "Observation of Picosecond Transient Raman Spectra by Asynchronous Fourier Transform Raman Spectroscopy". Applied Spectroscopy 52, n.º 1 (janeiro de 1998): 76–81. http://dx.doi.org/10.1366/0003702981942357.

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Asynchronous Fourier transform (FT) Raman spectroscopy with 100 picosecond time resolution has been developed. A signal-processing assembly required for time-resolved and transient Raman measurements consists of a picosecond Nd:YLF laser system, a gate circuit, and a low-pass filter, and it can be attached to any conventional continuous-scan FT-Raman spectrophotometer. The principle of signal processing employed in this method is almost the same as that of asynchronous pulsed-laser-excited FT-Raman spectroscopy. This method does not require synchronization between Raman excitation by probe laser pulses and sampling by the analog-to-digital converter. Transient Raman spectra have been obtained from the first excited singlet state of three anthracene derivatives in cyclohexane solutions and photoexcited poly( p-phenylenevinylene) [(C6H4CH=CH) n] by using 351 nm light (pulse width ã 70 ps) for photoexcitation and 1053 nm light (pulse width ã 100 ps) for Raman excitation.

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Nakagawa, Atsuhiro, Takayuki Hirano, Hidefumi Jokura, Hiroshi Uenohara, Tomohiro Ohki, Tokitada Hashimoto, Viren Menezes et al. "Pulsed holmium:yttrium-aluminum-garnet laser—induced liquid jet as a novel dissection device in neuroendoscopic surgery". Journal of Neurosurgery 101, n.º 1 (julho de 2004): 145–50. http://dx.doi.org/10.3171/jns.2004.101.1.0145.

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Object. A pressure-driven continuous jet of water has been reported to be a feasible tool for neuroendoscopic dissection owing to its superiority at selective tissue dissection in the absence of thermal effects. With respect to a safe, accurate dissection, however, continuous water flow may not be suitable for intraventricular use. The authors performed experiments aimed at solving problems associated with continuous flow by using a pulsed holmium:yttrium-aluminum-garnet (Ho:YAG) laser-induced liquid jet (LILJ). They present this candidate neuroendoscopic LILJ dissection system, having examined its mechanical characteristics and evaluated its controllability both in a tissue phantom and in a rabbit cadaveric ventricle wall. Methods. The LILJ generator was incorporated into the tip of a No. 4 French catheter so that the LILJ could be delivered via a neuroendoscope. Briefly, the LILJ was generated by irradiating an internally supplied column of physiological saline with a pulsed Ho:YAG laser (pulse duration time 350 µsec; laser energy 250–700 mJ/pulse) within a No. 4 French catheter (internal diameter 1 mm) and ejecting it from a metal nozzle (internal diameter 100 µm). The Ho:YAG laser energy pulses were conveyed by an optical fiber (core diameter 400 µm) at 3 Hz, whereas physiological saline (4°C) was supplied at a rate of 40 ml/hour. The mechanical characteristics of the pulsed LILJ were investigated using high-speed photography and pressure measurements; thermal effects and controllability were analyzed using an artificial tissue model (10% gelatin of 1 mm thickness). Finally, the ventricle wall of a rabbit cadaver was dissected using the LILJ. Jet pressure increased in accordance with laser energy from 0.1 to 2 bar; this translated into a penetration depth of 0.08 to 0.9 mm per shot in the ventricle wall of the rabbit cadaver. The gelatin phantom could be cut into the desired shape without significant thermal effects and in the intended manner, with a good surgical view. Conclusions. The present results show that the pulsed LILJ has the potential to become a safe and reliable dissecting method for endoscopic procedures.

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Pashina, Olesia, Daniil Ryabov, George Zograf, Sergey Makarov e Mihail Petrov. "Ultrafast laser heating of non-plasmonic nanocylinders". Journal of Physics: Conference Series 2015, n.º 1 (1 de novembro de 2021): 012104. http://dx.doi.org/10.1088/1742-6596/2015/1/012104.

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Abstract We develop a model describing non-equilibrium processes under the excitation of resonant semiconductor nanostructures with ultrashort laser pulses with a duration of about 100 fs. We focus on the heating effects related to pulsed excitation with account on free carriers generation, thermalization, and relaxation. The heat exchange between the electron and phonon system is treated within the two-temperature model. We applied the developed model to describing pulsed heating of silicon nanocylinder on top of a dielectric substrate. We come up with estimations of the thermal damage threshold of the considered structures which provides the limits for the experimental conditions and ensures thermal stability of the samples.

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