Journal articles: 'Pulsed laser irradiation'

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ZHANG, DUANMING, DAN LIU, ZHIHUA LI, SIPU HOU, BOMING YU, LI GUAN, XINYU TAN, and LI LI. "EFFECTS OF PLASMA SHIELDING ON PULSED LASER ABLATION." Modern Physics Letters B 20, no. 15 (June 30, 2006): 899–909. http://dx.doi.org/10.1142/s021798490601041x.

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We have developed a theoretical model which studies the characteristics of laser-plasma interaction, the effect of plasma shielding and plasma radiation in the ablation process. The model is used to simulate 25 ns square pulsed laser irradiation on YBa 2 Cu 3 O 7 targets, and pulsed laser with the pulse width of 25 ns (FWHM) irradiation on Ni targets. The evolution of the plasma length and the transmitted intensity are performed. The model shows the variation of ablation depth with energy density. Moreover, we obtain the dependence of the ablation depth on the number of laser pulses. The satisfactorily good agreement between our results and experimental results confirms that plasma shielding plays a relevant role in the ablation process.

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Ristic, Slavica, Suzana Polic, Bojana Radojkovic, and Joakim Striber. "Analysis of ceramics surface modification induced by pulsed laser treatment." Processing and Application of Ceramics 8, no. 1 (2014): 15–23. http://dx.doi.org/10.2298/pac1401015r.

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This paper presents the effects of laser light irradiation on the surface of ceramics dating from archaeological site Stubline (Obrenovac, Belgrade), Serbia. Two different pulsed lasers: TEA CO2 (10.6 ?m wavelength, pulse duration tp = 100 ns) and Nd:YAG (wavelengths 1064 nm and 532 nm, tp = 150 ps) have been used for surfaces treatment. Laser irradiation fluence was in the range of 1-20 J/cm2. Ceramics surface modifications induced by pulsed laser treatment were examined by scanning electron microscope, SEM, and the composition with energy dispersive X-ray, EDX, analysis. The tests were performed in order to obtain as much as possible information about the appropriate choice of materials and techniques for the further conservation and restoration of these items. The second objective was to determine the surface modifications induced by pulsed laser treatment above damage threshold (a safe cleaning laser fluence), as an important parameter in the use of lasers for the cleaning of cultural ceramic items.

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Kodama, Shuhei, Keita Shimada, Masayoshi Mizutani, and Tsunemoto Kuriyagawa. "Effects of Pulse Duration and Heat on Laser-Induced Periodic Surface Structures." International Journal of Automation Technology 14, no. 4 (July 5, 2020): 552–59. http://dx.doi.org/10.20965/ijat.2020.p0552.

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Compared with traditional nanotexturing methods, an ultrashort-pulsed laser is an efficient technology of fabricating nanostructures called laser-induced periodic surface structures (LIPSS) on material surfaces. LIPSS are easily fabricated when the pulse duration is shorter than collisional relaxation time (CRT). Accordingly, ultrashort-pulsed lasers have been mainly used to study LIPSS, but they unstably irradiate while requiring high costs. Although long-pulsed lasers have low cost and high stability, the phenomena (such as the effect of pulse duration, laser wavelength, and heat) of the LIPSS fabricated using short-pulsed lasers with the pulse duration close to the maximum CRT, which is greater than femtosecond, have not been clarified. However, the nanosecond pulse laser has been reported to produce LIPSS, but those were unclear and ununiform. In this study, the short-pulsed laser with the pulse duration of 20 ps, which is close to the maximum CRT, was employed to clarify the effects of pulse duration and heat on the fabrication of LIPSS and to solve problems associated with ultrashort-pulsed lasers. First, a finite-difference time-domain simulation was developed at 20-ps pulse duration to investigate the effects of irradiation conditions on the electric-field-intensity distribution. Subsequently, experiments were conducted using the 20-ps pulse laser by varying conditions. The aspect ratio of the LIPSS obtained was greater than that of the LIPSS fabricated using ultrashort-pulsed lasers, but LIPSS were not fabricated at 355- and 266-nm laser wavelength. In addition, the short-pulsed laser experienced thermal influences and a cooling material was effective for the fabrication of LIPSS with high-aspect-ratio. This demonstrates the effects of pulse duration close to the CRT and heat on the fabrication of LIPSS.

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Tetyorkin, V. V. "Conductivity type conversion in p-CdZnTe under pulsed laser irradiation." Semiconductor Physics Quantum Electronics and Optoelectronics 17, no. 3 (September 30, 2014): 291–94. http://dx.doi.org/10.15407/spqeo17.03.291.

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Jiang, Jianwei, Shaojuan Liu, Chunlei Wang, and Hongyan Zhang. "Overcoming Multidrug Resistance by On-Demand Intracellular Release of Doxorubicin and Verapamil." Journal of Nanomaterials 2018 (May 31, 2018): 1–7. http://dx.doi.org/10.1155/2018/3568190.

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Multidrug resistance (MDR) is one of the major obstacles to the successful application of cancer chemotherapy. Herein, we developed light-responsive doxorubicin-and-verapamil-coencapsulated gold liposomes to overcome MDR. Upon ns-pulsed laser irradiation, the highly confined thermal effect increased the permeability of the phospholipid bilayer, triggering the release of doxorubicin and verapamil, leading to high concentrations in cells. Free verapamil efficiently inhibited the membrane multidrug resistance proteins (MRPs), while the high concentration of doxorubicin saturated MRPs, thus overcoming MDR. We showed that nanosecond- (ns-) pulsed laser- (532 nm, 6 ns) induced doxorubicin release from gold liposomes depended on laser fluence and pulse number. More than 58% of the doxorubicin was released with a 10-pulse irradiation (100 mJ/cm2). Furthermore, ns laser pulses also liberated doxorubicin from endocytosed gold liposomes into the cytosol in MDA-MB-231-R cancer cells. The cytotoxicity of doxorubicin coencapsulated with verapamil was significantly enhanced upon laser irradiation. This study suggested that light-triggered on-demand release of chemotherapeutic agents and MRP inhibitors could be used advantageously to overcome multidrug resistance.

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SHIMAMURA, AKI, ARRI PRIIMAGI, JUN-ICHI MAMIYA, MOTOI KINOSHITA, TOMIKI IKEDA, and ATSUSHI SHISHIDO. "PHOTOINDUCED BENDING UPON PULSED IRRADIATION IN AZOBENZENE-CONTAINING CROSSLINKED LIQUID-CRYSTALLINE POLYMERS." Journal of Nonlinear Optical Physics & Materials 20, no. 04 (December 2011): 405–13. http://dx.doi.org/10.1142/s0218863511006200.

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We have investigated the photoresponsive behavior of homogeneously aligned low-azobenzene-concentration crosslinked liquid-crystalline polymers. We compared the thermal contraction and photocontraction of the films, and show that upon UV irradiation, they bend efficiently towards the actinic light source. The photoinduced bending is studied both under continuous-wave irradiation and irradiation with nanosecond pulses. Pulsed irradiation revealed that the photomechanical response can take place within sub-millisecond time scale, and that even a single laser pulse can cause the sample to bend.

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Dauletmuratov, B. K. "Features of a shock wave in CdTe by pulsed laser irradiation." Semiconductor Physics Quantum Electronics and Optoelectronics 14, no. 1 (February 28, 2011): 130–34. http://dx.doi.org/10.15407/spqeo14.01.130.

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Khaydarova, Anna, and Mariya Matrunchik. "Structure and Hardness of М2 High Speed Steel Modified by Pulsed Laser Irradiation." Materials Science Forum 942 (January 2019): 50–58. http://dx.doi.org/10.4028/www.scientific.net/msf.942.50.

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The paper studies the surface structure and microhardness of the coating modified by the pulsed laser irradiation. The coating is obtained by plasma-jet hard-facing of the AISI (American Iron and Steel Institute) М2 high speed steel powder. The modes of the laser irradiation differ in peaking capacity, pulse duration and diameters of the focused laser beam. It is demonstrated that the weld penetration shape factor depends on the laser beam fluence and the pulse duration. In its turn, the weld penetration shape factor effects the quality of obtained irradiation zones.

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Kodama, Shuhei, Shinya Suzuki, Akihiro Shibata, Keita Shimada, Masayoshi Mizutani, and Tsunemoto Kuriyagawa. "Effect of Crystal Structure on Fabrication of Fine Periodic Surface Structures with Short Pulsed Laser." International Journal of Automation Technology 12, no. 6 (November 5, 2018): 868–75. http://dx.doi.org/10.20965/ijat.2018.p0868.

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In recent years, nanostructures have been required for industry and medical services, to perform functions such as reduction in friction, control of wettability, and enhancement in biological affinity. Ultrashort pulsed lasers have been applied to meet these demands, and have been actively studied both experimentally and theoretically in terms of phenomena and principles. In this study, to clarify the phenomenon of the fabrication of laser-induced periodic surface structures (LIPSS), and its application to industry, experiments were conducted on SUS304, titanium, and nickel-phosphorus by a short pulsed laser that has a longer pulse duration, higher cost-effectiveness, and higher stability than ultrashort pulsed lasers. The results confirmed that while LIPSS were fabricated on Ti and Ni-P workpieces, a uniform fine periodic structure was not fabricated on the whole irradiated surface of SUS304, and crystal grain boundaries appeared with low energy density and irradiation number because SUS304 is an alloy composed of Fe, Cr, and Ni. Further, the short pulsed laser has a low power and long pulse duration, inducing the thermal effect. We clarified the effect of crystal structure on fabricating fine periodic surface structures with short pulsed laser.

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Zhenkun Yu, Zhenkun Yu, Hongbo He Hongbo He, Xu Li Xu Li, Hongji Qi Hongji Qi, and Wenwen Liu Wenwen Liu. "Stress mechanism of pulsed laser-driven damage in thin film under nanosecond ultraviolet laser irradiation." Chinese Optics Letters 11, no. 7 (2013): 073101–73102. http://dx.doi.org/10.3788/col201311.073101.

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Cao, Siqi, A. J. Pedraza, L. F. Allard, and D. H. Lowndes. "The effects of the atmosphere on the surface modification of alumina by pulsed-laser-irradiation." Journal of Materials Research 12, no. 7 (July 1997): 1747–54. http://dx.doi.org/10.1557/jmr.1997.0241.

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A near-surface thin layer is melted when alumina is pulsed-laser-irradiated in an Ar–4% H2 atmosphere or in air. A thin layer of amorphous phase forms when the substrates are irradiated in Ar–4% H2 at 1 to 1.3 J/cm2 with multiple laser pulses. Amorphous phase is also found in samples laser-irradiated in air and oxygen. After a laser pulse at an energy density of 1.6 J/cm2 or higher the melt solidifies epitaxially from the unmelted substrate with a cellular microstructure. There is a decrease in the cooling rate of the melt as the laser energy density is increased because more heat must be dissipated. The amorphous phase forms when the heat input due to the laser pulse produces a superheated melt that cools down sufficiently fast to avoid crystallization. Very small particles of aluminum in the laser-melted and subsequently solidified layer are observed only in samples laser-irradiated in an Ar–4% H2 atmosphere. In this reducing atmosphere, the alumina is possibly reduced to metallic aluminum which is mixed into the melt by the turbulence provoked by the laser pulses. The effects of these metallic particles on copper deposition when the irradiated substrates are immersed in an electroless bath are discussed.

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Barbora, Ayan, Oryan Bohar, Ariel Alexander Sivan, Eyal Magory, Ariel Nause, and Refael Minnes. "Higher pulse frequency of near-infrared laser irradiation increases penetration depth for novel biomedical applications." PLOS ONE 16, no. 1 (January 7, 2021): e0245350. http://dx.doi.org/10.1371/journal.pone.0245350.

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Background The clinical efficiency of laser treatments is limited by the low penetration of visible light used in certain procedures like photodynamic therapy (PDT). Second Harmonic Generation (SHG) PDT is an innovative technique to overcome this limitation that enables the use of Near Infrared (NIR) light instead of visible light. NIR frequency bands present an optical window for deeper penetration into biological tissue. In this research, we compare the penetration depths of 405 and 808 nm continuous wave (CW) lasers and 808 nm pulsed wave (PW) laser in two different modes (high and low frequency). Methods Increasing thicknesses of beef and chicken tissue samples were irradiated under CW and PW lasers to determine penetration depths. Results The 808 nm CW laser penetrates 2.3 and 2.4 times deeper than the 405 nm CW laser in beef and chicken samples, respectively. 808 nm PW (pulse frequency—500 Hz) penetrates deeper than CW laser at the same wavelength. Further, increasing the pulse frequency achieves higher penetration depths. High frequency 808 nm PW (pulse frequency—71.4 MHz) penetrates 7.4- and 6.0-times deeper than 405 nm CW laser in chicken and beef, respectively. Conclusions The results demonstrate the higher penetration depths of high frequency PW laser compared to low frequency PW laser, CW laser of the same wavelength and CW laser with half the wavelength. The results indicate that integrating SHG in the PDT process along with pulsed NIR light may allow the treatment of 6–7 times bigger tumours than conventional PDT using blue light.

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Chen, Defu, Ying Wang, Buhong Li, Huiyun Lin, Xuechun Lin, and Ying Gu. "Effects of pulse width and repetition rate of pulsed laser on kinetics and production of singlet oxygen luminescence." Journal of Innovative Optical Health Sciences 09, no. 06 (August 2016): 1650019. http://dx.doi.org/10.1142/s179354581650019x.

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Pulsed and continuous-wave (CW) lasers have been widely used as the light sources for photodynamic therapy (PDT) treatment. Singlet oxygen (1O2) is known to be a major cytotoxic agent in type-II PDT and can be directly detected by its near-infrared luminescence at 1270[Formula: see text]nm. As compared to CW laser excitation, the effects of pulse width and repetition rate of pulsed laser on the kinetics and production of 1O2 luminescence were quantitatively studied during photosensitization of Rose Bengal. Significant difference in kinetics of 1O2 luminescence was found under the excitation with various pulse widths of nanosecond, microsecond and CW irradiation with power of 20[Formula: see text]mW. The peak intensity and duration of 1O2 production varied with the pulse widths for pulsed laser excitation, while the 1O2 was generated continuously and its production reached a steady state with CW excitation. However, no significant difference ([Formula: see text]) in integral 1O2 production was observed. The results suggest that the PDT efficacy using pulsed laser may be identical to the CW laser with the same wavelength and the same average fluence rate below a threshold in solution.

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Mazhukin, V. I., M. G. Lobok, and I. Smurov. "Transient effects in pulsed laser irradiation." Applied Surface Science 253, no. 19 (July 2007): 7744–48. http://dx.doi.org/10.1016/j.apsusc.2007.02.086.

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Modest, M. F., and H. Abakians. "Heat Conduction in a Moving Semi-infinite Solid Subjected to Pulsed Laser Irradiation." Journal of Heat Transfer 108, no. 3 (August 1, 1986): 597–601. http://dx.doi.org/10.1115/1.3246977.

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Heat conduction in a moving semi-infinite medium subject to laser irradiation is considered. The body of knowledge of exact analytical solutions for Gaussian laser irradiation is expanded to include pulsed lasers, and laser beams that penetrate into the medium with exponential decay. For applications with complicated geometries (laser melting and evaporation), a simple integral method, based on one-dimensional diffusion, is presented, and its range of validity determined.

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Gaković, B., M. Trtica, S. Petrović, P. Panjan, M. Čekada, and Z. Samardžija. "Surface Structures Formed on AISI 420 Stainless Steel by Pulsed Laser Irradiation." Materials Science Forum 494 (September 2005): 309–14. http://dx.doi.org/10.4028/www.scientific.net/msf.494.309.

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The effects of TEA CO2 laser radiation on AISI 420 stainless steel and formed surface structures are studied. The laser energy density of 45.0 J/cm2 has modified the target surface. Qualitatively, the modifications of AISI 420 steel can be summarized as follows: change of color after action of one laser pulse; central zone of interaction in crater like form and periphery zone of interaction (for more than 10 laser pulses); appearance of grainy features and ablation rate of near 4 nm per laser pulse (action of 400 laser pulses); hydrodynamical effects like resolidified rim and droplets.

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Wang, Lu, De Guang Shang, Chong Gang Ren, Yu Bo Guo, and Tao Chen. "Effect of Temperature Induced by Laser Irradiation Processing on Fatigue Damage Repairing for Copper Thin Film." Advanced Materials Research 750-752 (August 2013): 2074–77. http://dx.doi.org/10.4028/www.scientific.net/amr.750-752.2074.

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Based on laser irradiation processing experiment for repairing damaged copper thin film specimens, the effect of temperature field induced by pulsed laser surface irradiation on fatigue damage repairing of copper thin film was studied by numerical simulation method. First the temperature field of copper thin film after laser irradiation was analyzed by ANSYS under different pulse energies and pulse numbers. Then the surface morphologies of copper thin film specimens were observed by optical microscope before and after laser surface irradiation. The results showed that laser irradiation processing has a better effect on fatigue damage repairing when the temperature induced by laser surface irradiation reaches about 1200 °C. A slightly melted morphology on the surface of copper thin film was observed in this case. In addition, except for the full healing of fatigue damage, the total fatigue life was increased about 2 times at the nominal stress level of 120MPa.

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Hamadi, Oday A. "Employment of Some Parameters to Enhance Laser-Drilling of Aluminum." Sultan Qaboos University Journal for Science [SQUJS] 10 (June 1, 2005): 93. http://dx.doi.org/10.24200/squjs.vol10iss0pp93-100.

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In this work, some parameters affecting drilling of aluminum samples by a pulsed Nd:YAG laser were studied. These parameters are multi-pulses irradiation, controlling sample temperature, low-pressure ambient and application of electric field on the sample. Results presented in this work explained that these parameters can enhance drilling process throughout increasing hole depth in aluminum samples at the same laser energy used for irradiation.

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Min, Min, Shuiting Ding, Xiao Yu, Shijian Zhang, Haowen Zhong, Gennady Efimovich Remnev, Xiaoyun Le, and Yu Zhou. "Investigation of the Effects of an Intense Pulsed Ion Beam on the Surface Melting of IN718 Superalloy Prepared with Selective Laser Melting." Metals 10, no. 9 (September 2, 2020): 1178. http://dx.doi.org/10.3390/met10091178.

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Intense pulsed ion beam irradiation on IN718 superalloy prepared with selective laser melting as an after-treatment for surface melting is introduced. It is demonstrated that intense pulsed ion beam composed of protons and carbon ions, with a maximum current density of 200 A/cm2 and a pulse length of 80 ns, can induce surface melting and the surface roughness changes significantly due to the generation of micro-defects and the flow of the molten surface. Irradiation experiments and thermal field simulation revealed that the energy density of the ion beam plays a predominant role in the irradiation effect—with low energy density, the flow of molten surface is too weak to smooth the fluctuations on the surface. With high energy density, the surface can be effectively melted and smoothened while micro-defects, such as craters, may be generated and can be flattened by an increased number of pulses. The research verified that for the surface melting with intense pulsed ion beam (IPIB), higher energy density should be used for stronger surface fluidity and a greater pulse number is also required for the curing of surface micro-defects.

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Фоминский, В. Ю., Р. И. Романов, A. A. Соловьев, И. С. Васильевский, Д. А. Сафонов, А. А. Иванов, П. В. Зинин, and В. П. Филоненко. "Особенности импульсного лазерного отжига пленок ВС-=SUB=-3-=/SUB=- на сапфировой подложке." Письма в журнал технической физики 45, no. 9 (2019): 26. http://dx.doi.org/10.21883/pjtf.2019.09.47709.17722.

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The morphology, chemical composition, microstructure and electrical properties of BC3 thin films subjected to melting by a nanosecond laser pulse were investigated. The original films were formed by pulsed laser co-deposition of B and C on a sapphire substrate at 150 and 350 °C. Morphological changes in the films depended on their initial structure. However, the structure “frozen” after irradiation in both films was attributed to the B-saturated graphite-like phase, the local composition of which varied due to the formation of inclusions of amorphous boron carbide. Before and after irradiation, the films showed a weakly decreasing dependence of the sheet resistance with increasing temperature from 4.2 to 330 K. After pulsed laser irradiation, the sheet resistance of the films decreased by ~ 2.6 times.

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Teodorescu, Valentin Serban, Cornel Ghica, Adrian Valentin Maraloiu, Mihai Vlaicu, Andrei Kuncser, Magdalena Lidia Ciurea, Ionel Stavarache, et al. "Nanostructuring of GeTiO amorphous films by pulsed laser irradiation." Beilstein Journal of Nanotechnology 6 (April 7, 2015): 893–900. http://dx.doi.org/10.3762/bjnano.6.92.

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Laser pulse processing of surfaces and thin films is a useful tool for amorphous thin films crystallization, surface nanostructuring, phase transformation and modification of physical properties of thin films. Here we show the effects of nanostructuring produced at the surface and under the surface of amorphous GeTiO films through laser pulses using fluences of 10–30 mJ/cm2. The GeTiO films were obtained by RF magnetron sputtering with 50:50 initial atomic ratio of Ge:TiO2. Laser irradiation was performed by using the fourth harmonic (266 nm) of a Nd:YAG laser. The laser-induced nanostructuring results in two effects, the first one is the appearance of a wave-like topography at the film surface, with a periodicity of 200 nm and the second one is the structure modification of a layer under the film surface, at a depth that is related to the absorption length of the laser radiation. The periodicity of the wave-like relief is smaller than the laser wavelength. In the modified layer, the Ge atoms are segregated in spherical amorphous nanoparticles as a result of the fast diffusion of Ge atoms in the amorphous GeTiO matrix. The temperature estimation of the film surface during the laser pulses shows a maximum of about 500 °C, which is much lower than the melting temperature of the GeTiO matrix. GeO gas is formed at laser fluences higher than 20 mJ/cm2 and produces nanovoids in the laser-modified layer at the film surface. A glass transition at low temperatures could happen in the amorphous GeTiO film, which explains the formation of the wave-like topography. The very high Ge diffusivity during the laser pulse action, which is characteristic for liquids, cannot be reached in a viscous matrix. Our experiments show that the diffusivity of atomic and molecular species such as Ge and GeO is very much enhanced in the presence of the laser pulse field. Consequently, the fast diffusion drives the formation of amorphous Ge nanoparticles through the segregation of Ge atoms in the GeTiO matrix. The nanostructuring effects induced by the laser irradiation can be used in functionalizing the surface of the films.

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SHEN, MENGYAN. "NANOSTRUCTURING SOLID SURFACES WITH FEMTOSECOND LASER IRRADIATIONS FOR APPLICATIONS." Modern Physics Letters B 24, no. 03 (January 30, 2010): 257–69. http://dx.doi.org/10.1142/s0217984910022457.

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Pulsed laser-assisted etching is a simple but effective method for fabricating small regular structures directly onto a surface. We have successfully fabricated submicro- or nano-meter sized spikes on a solid surface immersed in liquids with femtosecond laser pulse irradiations. This method is applicable to different metals such as stainless steel, copper, titanium, cobalt, as well as different semiconductors, such as Si and GaAs. The femtosecond laser method is much faster than other methods. We can control the experimental conditions to design and fabricate nanostructures in different materials and on the surfaces with different morphologies. Here, we discuss the nanostructures formation with femtosecond pulse laser irradiations, and introduce our results of the nanostructure for applications in sensing, biology and artificial photosynthesis. The femtosecond laser irradiation technique can efficiently integrate metal, semiconductor and polymer nanostructures in various small devices to leverage the expertise in other research fields and applications.

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Polman, A., W. C. Sinke, M. J. Uttormark, and Michael O. Thompson. "Pulsed-laser induced transient phase transformations at the Si–H2O interface." Journal of Materials Research 4, no. 4 (August 1989): 843–56. http://dx.doi.org/10.1557/jmr.1989.0843.

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Phase transformations at the Si–H2O interface, induced by nanosecond pulsed laser irradiation, were studied in real time. Si samples were irradiated using a 4 ns pulse from a Q-switched frequency-doubled Nd:YAG laser while immersed in the transparent liquid. Using time-resolved conductivity and reflectivity techniques, in combination with modeling of optical parameters and heat flow, transient processes in the Si, the H2O, and at the interface have been unraveled. In the liquid, local rapid heating occurs as a result of heat flow across the interface, and formation of a low-density steam phase occurs on a nanosecond timescale. Expansion of this phase is followed by a collapse after 200 ns. These rapid phase transformations in the water initiate a shock wave with a pressure of 0.4± 0.3 kbar. Transient phase transformations and the heat flow into the water during the laser pulse influence the energy coupling into the sample, resulting in an effective laser pulse shortening. The pulse shortening and the additional heat flow into the water during solidification result in a 30% enhancement of the solidification velocity for 270 nm deep melts. Cross-section transmission electron microscopy data reveal that the Si surface is planar after irradiation and is inert to chemical reactions during irradiation. Recent experiments described in the literature concerning pulsed-laser induced synthesis at the solid-liquid interface are reviewed and discussed in the context of the fundamental phenomena presently observed.

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Suzuki, M., C. Kato, S. Kawashima, and K. Shinkai. "Clinical and Histological Study on Direct Pulp Capping With CO2 Laser Irradiation in Human Teeth." Operative Dentistry 44, no. 4 (July 1, 2019): 336–47. http://dx.doi.org/10.2341/18-030-c.

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SUMMARYThe study aimed to histologically evaluate wound healing of exposed human pulp on direct pulp capping using super-pulsed CO2 laser preirradiation. In this single-blind clinical trial, 28 third molar teeth of 17 volunteers were randomly capped with either CO2 laser irradiation (n=14) or Dycal (calcium hydroxide cement; n=14) and restored using resin composite. The laser was operated in super-pulsed mode (pulse duration, 0.2 ms; interval, 5.8 ms; 0.003 J/pulse). The irradiation conditions were a power output of 0.5 W, an irradiation time of 15 seconds, repeat mode (10-ms irradiation and 10-ms intervals, for a total beam exposure time of 7.5 seconds), total applied energy of 3.75 J, and an activated air-cooling system. Each tooth was extracted at six or 12 months posttreatment and prepared for histological evaluation. We evaluated the parameters of pulp tissue disorganization, inflammatory cell infiltration, reparative dentin formation (RDF), and bacterial penetration. There were no significant differences between groups for all parameters at each postoperative period (Mann-Whitney U-test, p>0.05). CO2 laser irradiation completely controlled bleeding and exudate from the exposed pulp. The CO2 laser group had a tendency to delay RDF compared with the Dycal group, but 4 of 7 teeth from the CO2 laser group showed a complete dentin bridge at 12 months posttreatment.

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Suzuki, Shinichi, Daisuke Suzuki, and Tatsuhiro Ito. "OS8-2-1 Generation of underwater focusing shock wave by pulsed laser irradiation." Abstracts of ATEM : International Conference on Advanced Technology in Experimental Mechanics : Asian Conference on Experimental Mechanics 2007.6 (2007): _OS8–2–1–1—_OS8–2–1–6. http://dx.doi.org/10.1299/jsmeatem.2007.6._os8-2-1-1.

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Neimash, V. B., A. O. Goushcha, L. L. Fedorenko, P. Ye Shepelyavyi, V. V. Strelchuk, A. S. Nikolenko, M. V. Isaiev, and A. G. Kuzmich. "Role of Laser Power, Wavelength, and Pulse Duration in Laser Assisted Tin-Induced Crystallization of Amorphous Silicon." Journal of Nanomaterials 2018 (2018): 1–11. http://dx.doi.org/10.1155/2018/1243685.

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This work describes tin-induced crystallization of amorphous silicon studied with Raman spectroscopy in thin-film structures Si-Sn-Si irradiated with pulsed laser light. We have found and analyzed dependencies of the nanocrystals’ size and concentration on the laser pulse intensity for 10 ns and 150 μm duration laser pulses at the wavelengths of 535 nm and 1070 nm. Efficient transformation of the amorphous silicon into a crystalline phase during the 10 ns time interval of the acting laser pulse in the 200 nm thickness films of the amorphous silicon was demonstrated. The results were analyzed theoretically by modeling the spatial and temporal distribution of temperature in the amorphous silicon sample within the laser spot location. Simulations confirmed importance of light absorption depth (irradiation wavelength) in formation and evolution of the temperature profile that affects the crystallization processes in irradiated structures.

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Stafast, H., and M. Von Przychowski. "Evaporation of solids by pulsed laser irradiation." Applied Surface Science 36, no. 1-4 (January 1989): 150–56. http://dx.doi.org/10.1016/0169-4332(89)90908-2.

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Baeri, P., L. Torrisi, N. Marino, and G. Foti. "Ablation of hydroxyapatite by pulsed laser irradiation." Applied Surface Science 54 (January 1992): 210–14. http://dx.doi.org/10.1016/0169-4332(92)90046-z.

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Torrisi, L., F. Caridi, A. M. Visco, and N. Campo. "Polyethylene welding by pulsed visible laser irradiation." Applied Surface Science 257, no. 7 (January 2011): 2567–75. http://dx.doi.org/10.1016/j.apsusc.2010.10.023.

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Athanassiou, A., K. Lakiotaki, M. Kalyva, S. Georgiou, and C. Fotakis. "Photoswitches operating upon ns pulsed laser irradiation." Applied Surface Science 248, no. 1-4 (July 2005): 56–61. http://dx.doi.org/10.1016/j.apsusc.2005.03.077.

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Hiraoka, H. "Pulsed UV laser irradiation of polymer surfaces." Journal of Photochemistry and Photobiology A: Chemistry 92, no. 1-2 (December 1995): 129–33. http://dx.doi.org/10.1016/1010-6030(95)04165-7.

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Ortega-Mendoza, Gabriel, Oscar Goiz, Alfonso Padilla-Vivanco, Carina Toxqui-Quitl, Placido Zaca-Moran, and Fernando Chavez. "Photofusion and Disaggregation of Silver Nanoparticles Suspended in Ethanol by Laser Irradiation." Current Nanoscience 14, no. 1 (December 22, 2017): 50–53. http://dx.doi.org/10.2174/1573413713666171002124415.

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Background: Metal nanoparticles have been widely investigated due to their unique optical, mechanical, and chemical properties compared with those of the same bulk material. These properties can be tuned by controlling their size or shape, in this sense, several nanomaterials have been obtained by means of both chemical and physical methods. For instance, silver nanoparticles have been obtained in liquid media by using laser ablation or chemical reduction techniques. Another way to obtain a colloidal silver nanoparticles is through the well-known pulsed laser irradiation method which can produce a stable colloidal solution in a few minutes of irradiation and without stabilizing molecules or ligands. Methods: Silver nanopowder suspended in ethanol was irradiated with a pulsed laser at 532 nm via optical fiber. Previously, the fiber was prepared by cleaving and removing its coating and then placed in the middle of a cell. The pulse width was 15 ns and the pulse repetition frequency was 10 kHz. Scanning and transmission electron microscopes were used to observe the silver nanoparticles before and after laser irradiation, respectively. The samples were analyzed by means of UV-Vis spectrophotometer to observe the absorption spectra. Results: The absorption spectra show that particle size distribution increases according to the irradiation time. The colloidal solution showed a color change (from gray to yellow) after having irradiated it for 5 minutes. From TEM images, it can be observed that silver nanopowder was transformed to semispherical particles with diameters smaller than 1μm, however, due to the wide particle size distribution the colloidal solution was centrifuged for 30 min to separate the nanoparticles. Conclusion: The pulsed laser irradiation method via optical fiber was successfully used to obtain a stable yellow colloidal solution. Photomelting, photofusion, and photofragmentation are the responsible phenomena for the change in morphology and size of the silver nanopowder.

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Qi, Li Tao. "Single Femtosecond Laser Pulse Irradiation of Silicon on Different Crystallographic Facet Planes." Advanced Materials Research 314-316 (August 2011): 1885–88. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.1885.

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Experiment on ablation of silicon wafer on different crystallographic facet planes by single laser pulse irradiation was carried out with a femtosecond pulsed laser operating at a wavelength of 780 nm and a pulse width of 160 fs. The quality and morphology of the laser ablated silicon surface were evaluated by atomic force microscopy. The ablation threshold fluences on different crystallographic facet planes were obtained through the relationship between the squared diameter of the craters and pulse energy. The effects of different crystallographic facet planes of silicon wafer on the process of femtosecond laser ablation of silicon wafer were studied.

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Kostrubiec, F., and M. Walczak. "Microhardness of the Surface Layer of Tungsten and Molybdenum After Recrystallization With Laser Radiation." Journal of Engineering Materials and Technology 113, no. 1 (January 1, 1991): 130–34. http://dx.doi.org/10.1115/1.2903368.

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We present results of microhardness measurements in melted local regions in molybdenum and tungsten. Microhardness has been measured by the Vickers method. Melted regions have been produced by pulsed Nd-glass laser. The emphasis is on correlation between conditions of recrystallization (energy of laser beam and method of irradiation-single pulse or multiple pulse) and the microhardness value.

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Zhu, Ruixue, Tatiana Avsievich, Alexander Bykov, Alexey Popov, and Igor Meglinski. "Influence of Pulsed He–Ne Laser Irradiation on the Red Blood Cell Interaction Studied by Optical Tweezers." Micromachines 10, no. 12 (December 5, 2019): 853. http://dx.doi.org/10.3390/mi10120853.

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Optical Tweezers (OT), as a revolutionary innovation in laser physics, has been extremely useful in studying cell interaction dynamics at a single-cell level. The reversible aggregation process of red blood cells (RBCs) has an important influence on blood rheological properties, but the underlying mechanism has not been fully understood. The regulating effects of low-level laser irradiation on blood rheological properties have been reported. However, the influence of pulsed laser irradiation, and the origin of laser irradiation effects on the interaction between RBCs remain unclear. In this study, RBC interaction was assessed in detail with OT. The effects of both continuous and pulsed low-level He–Ne laser irradiation on RBC aggregation was investigated within a short irradiation period (up to 300 s). The results indicate stronger intercellular interaction between RBCs in the enforced disaggregation process, and both the cell contact time and the initial contact area between two RBCs showed an impact on the measured disaggregation force. Meanwhile, the RBC aggregation force that was independent to measurement conditions decreased after a short time of pulsed He–Ne laser irradiation. These results provide new insights into the understanding of the RBC interaction mechanism and laser irradiation effects on blood properties.

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OGAWA, Keiji, Heisaburo NAKAGAWA, and Tatsurou NAKABOU. "A011 Pulsed Laser Milling Integrated Die and Mold Machining : Experimental Analysis of Laser Irradiation Method on Process Performance." Proceedings of International Conference on Leading Edge Manufacturing in 21st century : LEM21 2013.7 (2013): 51–54. http://dx.doi.org/10.1299/jsmelem.2013.7.51.

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HE, DEYAN, WENWU WANG, HAIJUN JIA, and ERQING XIE. "FORMATION OF OXYGEN-FREE GADOLINIUM SILICIDE LAYER BY ION IMPLANTATION AND PULSED EXCIMER LASER IRRADIATION." International Journal of Modern Physics B 16, no. 28n29 (November 20, 2002): 4331–34. http://dx.doi.org/10.1142/s0217979202015376.

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Buried gadolinium silicide layer was prepared by ion implantation of Gd into n-type Si (100) wafer. It was shown that GdSi 2 grains have been formed during Gd + implantation. An oxygen-free continuous layer of (112) oriented GdSi 2 was obtained after irradiating the sample using a pulsed excimer laser. Comparing with conventional thermal annealing pulsed excimer laser irradiation at energy densities close to the threshold for melting Si surface layer could prepare oxygen-free GdSi 2 buried layer within a preferred region.

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Cao, Siqi, A. J. Pedraza, L. F. Allard, and D. H. Lowndes. "Formation of polytype microstructure in pulsed-laser-irradiated sapphire substrates." Proceedings, annual meeting, Electron Microscopy Society of America 53 (August 13, 1995): 344–45. http://dx.doi.org/10.1017/s0424820100138099.

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Surface modifications of wide-gap materials are produced by pulsed laser irradiation. Under given conditions, these near-surface modifications can promote adhesion enhancement of deposited thin film materials, and activation for electroless deposition. AIN decomposes during laser irradiation leaving a metallic film on the surface. High density dislocations were observed in the surface layer of AIN that was laser melted but not decomposed. The laser melted alumina becomes amorphous at a laser energy density of ~1J/cm2. In sapphire, γ-alumina is formed when the sample is laser irradiated in Ar/4%H2. Here, we report the formation of a new structure in laser-irradiated sapphire.Optically polished c-axis sapphire substrates were laser-irradiated in an Ar/4%H2 atmosphere at 4J/cm2 energy density, using a 308 nm-wavelength laser with a pulse duration of ~40 ns. Sapphire (A12O3) has a space group R 3 c and can be described as an hcp structure having oxygen and aluminum layers alternately stacking along the c-axis.

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Zhang and, Z. M., and D. H. Chen. "Thermal Analysis of Multiphoton Absorption at 193 nm in Volume-Absorbing Glass." Journal of Heat Transfer 124, no. 2 (August 23, 2001): 391–94. http://dx.doi.org/10.1115/1.1447940.

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Two-photon absorption in volume-absorbing materials may be significant for high-power, short-pulse excimer laser irradiation. In the present work, the effects of two-photon absorption on the laser intensity propagation and the penetration depth are investigated. The temperature history of a glass plate during pulsed ultraviolet (UV) laser heating is predicted. The results show that the two-photon absorption can compress the volume-absorbing effect to surface absorption and increase the peak temperature on the glass surface. This will reduce the damage threshold, increase the energy loss, and reduce the accuracy of pulsed-laser calorimeters.

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Gutiérrez-Fernández, Edgar, Tiberio Ezquerra, Aurora Nogales, and Esther Rebollar. "Straightforward Patterning of Functional Polymers by Sequential Nanosecond Pulsed Laser Irradiation." Nanomaterials 11, no. 5 (April 27, 2021): 1123. http://dx.doi.org/10.3390/nano11051123.

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Laser-based methods have demonstrated to be effective in the fabrication of surface micro- and nanostructures, which have a wide range of applications, such as cell culture, sensors or controlled wettability. One laser-based technique used for micro- and nanostructuring of surfaces is the formation of laser-induced periodic surface structures (LIPSS). LIPSS are formed upon repetitive irradiation at fluences well below the ablation threshold and in particular, linear structures are formed in the case of irradiation with linearly polarized laser beams. In this work, we report on the simple fabrication of a library of ordered nanostructures in a polymer surface by repeated irradiation using a nanosecond pulsed laser operating in the UV and visible region in order to obtain nanoscale-controlled functionality. By using a combination of pulses at different wavelengths and sequential irradiation with different polarization orientations, it is possible to obtain different geometries of nanostructures, in particular linear gratings, grids and arrays of nanodots. We use this experimental approach to nanostructure the semiconductor polymer poly(3-hexylthiophene) (P3HT) and the ferroelectric copolymer poly[(vinylidenefluoride-co-trifluoroethylene] (P(VDF-TrFE)) since nanogratings in semiconductor polymers, such as P3HT and nanodots, in ferroelectric systems are viewed as systems with potential applications in organic photovoltaics or non-volatile memories.

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Pimpang, Pichitchai, Duangmanee Wongratanaphisan, Atcharawan Gardchareon, and Supab Choopun. "Size Reduction of Gold Nanoparticles by Pulsed Laser Ablation and Re-Irradiation in Water Media." Materials Science Forum 695 (July 2011): 174–77. http://dx.doi.org/10.4028/www.scientific.net/msf.695.174.

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Gold nanoparticles (Au NPs) were prepared by using pulsed laser ablation with and without cover slide. The cover slide was used to confine atoms/ions in order to reach supersaturation condition. The obtained Au NPs were investigated by UV-vis spectroscopy, transmission electron microscopy (TEM), and zeta potential measurement. The absorbance spectra exhibited its absorption peak at around 520 nm for both Au NPs ablating with and without cover slide. It was found that Au NPs ablating with cover slide exhibited smaller size and size distribution (10.6 ± 5.9 nm) than those of without cover slide (34.1 ± 21.5 nm) at laser power of 5.00 mJ/pulse. This is due to supersaturation effect and re-irradiation effect caused by cover slide that trapped atoms/ions of gold and trapped Au NPs, respectively. Also, the zeta potential of Au NPs had a negative value suggesting negative surface charge. The lowest zeta potential was observed for Au NPs ablating with cover slide at 5.00 mJ/pulse and it was in consistent with an observation of the highest pH value. In addition, the Au NPs ablating with cover slide at 5.00 mJ/pulse showed the least change with time indicating the most stable Au NPs which was in consistent with the lowest zeta potential results. Thus, pulsed laser re-irradiation could be used for size reduction of Au NPs prepared by pulsed laser ablation in water media.

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Louh, Rong-Fuh, and Relva C. Buchanan. "Hole pattern formation in unfired ceramic sheets by pulsed Nd:YAG laser." Journal of Materials Research 5, no. 4 (April 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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Ushakov, N. M., and I. D. Kosobudskii. "Impact of UV pulsed laser radiation and of the electron flow on dielectric states of polymer composite nanomaterial based on LDPE matrix." Физика и техника полупроводников 52, no. 4 (2018): 488. http://dx.doi.org/10.21883/ftp.2018.04.45837.26.

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AbstractThe influence of the soft electron flow and irradiating pulsed UV laser on dielectric states of polymer composite nanomaterial based on LDPE matrix is experimentally studied. It was shown that irradiation of the samples LDPE–ZnO by electron beam (10 keV) for 10–15 minutes gives rise the appearance of the horizontal portion of the temperature dependence of capacitance (permittivity) and to memory effect (slow relaxation of dielectric situation within a few days). Irradiation with pulsed UV laser of the LDPE–CdS sample allows you to switch into a conducting state and return it to their original state upon application of a weak electric field. The observed phenomena may find practical applications for the polymer electronic memories and switching devices.

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Momoki, Ko, Kunimitsu Takahashi, Kyosuke Kobinata, Yoshikazu Kobayashi, Akihito Kawai, and Jiwang Yan. "Generating Silicon Nanofiber Clusters from Grinding Sludge by Millisecond Pulsed Laser Irradiation." Nanomaterials 10, no. 4 (April 23, 2020): 812. http://dx.doi.org/10.3390/nano10040812.

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Silicon nanofiber clusters were successfully generated by the irradiation of millisecond pulsed laser light on silicon sludge disposed from wafer back-grinding processes. It was found that the size, intensity, and growing speed of the laser-induced plume varied with the gas pressure, while the size and morphology of the nanofibers were dependent on the laser pulse duration. The generated nanofibers were mainly amorphous with crystalline nanoparticles on their tips. The crystallinity and oxidation degree of the nanofibers depended on the preheating conditions of the silicon sludge. This study demonstrated the possibility of changing silicon waste into functional nanomaterials, which are possibly useful for fabricating high-performance lithium-ion battery electrodes.

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Malmqvist, Sebastian, Anders Liljeborg, Talat Qadri, Gunnar Johannsen, and Annsofi Johannsen. "Using 445 nm and 970 nm Lasers on Dental Implants—An In Vitro Study on Change in Temperature and Surface Alterations." Materials 12, no. 23 (November 27, 2019): 3934. http://dx.doi.org/10.3390/ma12233934.

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The aim of this study was to evaluate the safety of using a 445 nm laser on dental implants by comparing it with a laser with 970 nm wavelength. Two models, a pig mandible and glass ionomer cement, were used to evaluate the temperature increase in dental implants during laser irradiation with both wavelengths. Temperature was measured every second at four different places on the dental implants. Different power settings, effects of water cooling, distance of the laser fibre to the dental implant and continuous comparison to a pulsed laser beam were tested. Surface alterations on titanium discs after laser irradiation for 4 min at 2.0 W, were analysed in a scanning electron microscope (SEM). The maximum temperature and time to reach each of the thresholds were comparable between the 445 nm and 970 nm lasers. Neither the 445 nm nor the 970 nm wavelength showed any signs of surface alterations on the titanium discs. Using a 445 nm laser on dental implants is as safe as using a 970 nm laser, in terms of temperature increase and surface alterations. Applying a generous amount of cooling water and irradiating in short intervals is important when using lasers on dental implants.

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Babayan, Nelly, Natalia Vorobyeva, Bagrat Grigoryan, Anna Grekhova, Margarita Pustovalova, Sofya Rodneva, Yuriy Fedotov, Gohar Tsakanova, Rouben Aroutiounian, and Andreyan Osipov. "Low Repair Capacity of DNA Double-Strand Breaks Induced by Laser-Driven Ultrashort Electron Beams in Cancer Cells." International Journal of Molecular Sciences 21, no. 24 (December 14, 2020): 9488. http://dx.doi.org/10.3390/ijms21249488.

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Laser-driven accelerators allow to generate ultrashort (from femto- to picoseconds) high peak dose-rate (up to tens of GGy/s) accelerated particle beams. However, the radiobiological effects of ultrashort pulsed irradiation are still poorly studied. The aim of this work was to compare the formation and elimination of γH2AX and 53BP1 foci (well known markers for DNA double-strand breaks (DSBs)) in Hela cells exposed to ultrashort pulsed electron beams generated by Advanced Research Electron Accelerator Laboratory (AREAL) accelerator (electron energy 3.6 MeV, pulse duration 450 fs, pulse repetition rates 2 or 20 Hz) and quasi-continuous radiation generated by Varian accelerator (electron energy 4 MeV) at doses of 250–1000 mGy. Additionally, a study on the dose–response relationships of changes in the number of residual γH2AX foci in HeLa and A549 cells 24 h after irradiation at doses of 500–10,000 mGy were performed. We found no statistically significant differences in γH2AX and 53BP1 foci yields at 1 h after exposure to 2 Hz ultrashort pulse vs. quasi-continuous radiations. In contrast, 20 Hz ultrashort pulse irradiation resulted in 1.27-fold higher foci yields as compared to the quasi-continuous one. After 24 h of pulse irradiation at doses of 500–10,000 mGy the number of residual γH2AX foci in Hela and A549 cells was 1.7–2.9 times higher compared to that of quasi-continuous irradiation. Overall, the obtained results suggest the slower repair rate for DSBs induced by ultrashort pulse irradiation in comparison to DSBs induced by quasi-continuous irradiation.

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Sorescu, M., and E. T. Knobbe. "Effect of pulsed excimer laser irradiation on the magnetic anisotropy of iron-base and nickel-iron-base metallic glasses." Journal of Materials Research 8, no. 12 (December 1993): 3078–84. http://dx.doi.org/10.1557/jmr.1993.3078.

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The present work has examined the effect of pulsed excimer laser irradiation (λ = 308 nm, τ = 26 ns, E = 100 mJ/pulse, N = 1, 5, 10 laser pulses/spot, repetition rate 1 Hz) on the magnetic anisotropy of Fe81B13.5Si3.5C2, Fe78B13Si9, Fe40Ni38Mo4B18, and Fe40Ni40P14B6 metallic glasses. The transmission Mössbauer spectra yielded the intensity ratio R21 of the second to the first line as a function of the number of applied laser pulses. On these grounds, it was found that in the higher magnetostriction samples, controlled changes in the magnetic anisotropy could be induced without onset of bulk crystallization; in the lower magnetostriction samples, a random distribution of the magnetic moment directions was obtained. The conversion electron Mössbauer spectra were characteristic of the amorphous state but showed the same texture as the nonirradiated samples. SEM examinations of the laser-treated surfaces revealed the presence of molten zones subsequently solidified. It is suggested that the correspondingly induced stresses may account for the observed changes in the bulk magnetization orientation, and the model of closure domain structure is supported.

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Yang, Li Jun, and Yang Wang. "Affected Characteristics Analysis of the Pulsed Laser Forming of Metal Sheet." Key Engineering Materials 375-376 (March 2008): 333–37. http://dx.doi.org/10.4028/www.scientific.net/kem.375-376.333.

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Laser forming of metal sheet is a forming technology of sheet without a die that the sheet is deformed by internal thermal stress induced by partially irradiation of a laser beam. In this paper, the bending behavior of common stainless steel 1Cr18Ni9 sheet is studied after being irradiated by straight line with a Nd:YAG pulsed laser beam. The aim of the investigation is to find out the relationship of the physical behaviors of heat affected zone (HAZ) with the pulse parameters of the laser. Through the analysis of the fundamental theory of pulsed laser affected, this paper shows the affected characteristics of metal sheet with pulsed laser forming. The results show that the microstructure of HAZ of pulsed laser scanned is layered, and the micro-hardness is improved than that in matrix. The microstructures show that the deformed grain structure is inhomogeneous, that caused the grain sizes and grain orientations in HAZ to become different. By qualitative analysis of experimental result, the conclusion obtained may provide basis for theoretical investigation and possible industrial application of laser forming process in the future.

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Shigeo, Tanaka, and Tsuyoshi Nishisaka. "Ocular damage induced by pulsed laser irradiation (N):." JOURNAL OF JAPAN SOCIETY FOR LASER SURGERY AND MEDICINE 17, Supplement (1996): 243–46. http://dx.doi.org/10.2530/jslsm1980.17.supplement_243.

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Fiedler, D. M., G. Schnitzhofer, H. Walt, D. Dobler-Girdziunaite, and B. Krammer. "Photodynamic Cytotoxicity Enhancement by Pulsed Diode Laser Irradiation." Laser-Medizin: eine interdisziplinäre Zeitschrift ; Praxis, Klinik, Forschung 15, no. 3 (September 2000): 107–14. http://dx.doi.org/10.1016/s0938-765x(00)80004-8.

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Journal articles on the topic 'Pulsed laser irradiation'

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