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Nd:YAG Lasers Operating at 1064nm and 946nm by Direct Pumping and Thermally Boosted Pumping

XU Chang-Wen,WEI Zhi-Yi,HE Kun-Na,LI De-Hua,ZHANG Yong-Dong,ZHANGZhi-Guo,

中国物理快报 , 2009,
Abstract: We demonstrate a 1064nm Nd:YAG laser by directly pumping into the upper lasing level with a tunable Ti:sapphire laser. The valid wavelength is demonstrated at 868.3nm, 875.2nm, 883.8nm, and 885.5nm, respectively. To our knowledge, this is the first time that 1064nm Nd:YAG laser pumped by 875.2nm laser. In addition, laser wavelength at 946nm is also generated by direct pumping together with traditional pumping.
Diagnostic Study of Nickel Plasma Produced by Fundamental (1064 nm) and Second Harmonics (532 nm) of an Nd: YAG Laser  [PDF]
M. Hanif, M. Salik, M. A. Baig
Journal of Modern Physics (JMP) , 2012, DOI: 10.4236/jmp.2012.330203
Abstract: In the present work, we have studied the spatial evolution of the nickel alloy plasma produced by the fundamental (1064 nm) and second (532 nm) harmonics of a Q-switched Nd: YAG laser by placing the target material in air at atmospheric pressure. The four Ni I lines at 335.10 nm, 394.61 nm, 481.19 nm and 515.57 nm are used for the determination of electron temperature (Te) using Boltzmann plot method. The electron temperature is calculated as a function of distance from the target surface for both modes of Nd: YAG laser. In case of fundamental (1064 nm) mode of laser, the temperature varies from 13700 - 10270 K as the distance is varied from 0 to 2 mm. Whereas, in the case of second (532 nm) mode of laser it varies from 13270 - 9660 K for the same distance variation. The electron temperature has also been determined by varying the energy of the laser from 90 to 116 mJ, for the fundamental (1064 nm) harmonic and from 58 to 79 mJ for the second (532 nm) harmonics of the laser. The temperature increases from 14192 to 15765 K in the first case and from 13170 to 14800 K for the second case. We have also studied the spatial behavior of the electron number density in the plasma plume. The electron number density (Ne) in the case of fundamental (1064 nm) harmonic of the laser having pulse energy 125 mJ varies from 2.81 × 1016 to 9.81 × 1015 cm-3 at distances of 0 mm to 2.0 mm, whereas, in the case of second (532 nm) harmonic, with pulse energy 75 mJ it varies from 3.67 × 1016 to 1.48 × 1016 cm-3 for the same distance variation by taking Ni I line at 227.20 nm in both the cases.
Utilization of Nd:YAG Laser (1064 nm) in the treatment of dermatosis papulosa nigra in some Sudanese patients.
Shaza Mohammed Yousif,Nafie A. Al-Muslet,Nagi Zarif Malati
Clinical Dermatology , 2009,
Abstract: Introduction: Skin of phototypes IV to VI according to Fitzpatrick represents the majority of the world's population. Clinically, the features of photoaging in African can include fine wrinkling, mottled pigmentation, and dermatosis papulosa nigra (DPN). All studies have confirmed the effectiveness and low risk of complication associated with use of Nd: YAG laser in dark skin patients. Objectives: This study aimed to detect the effectiveness of Nd: YAG laser, 1064 nm, with specific laser parameters, in the treatment of dermatosis papulosa nigra (DPN) in some Sudanese patients. Material and methods: Twenty patients, clinically diagnosed as cases of dermatosis papulosa nigra, were selected from different dermatology clinics in Khartoum state and were considered as study population. Nd: YAG laser, with 1064 nm wavelength, was used in this study. The laser parameters were: non-contact applications of bare fiber, power of 25 Watt and duty cycle of 0.2 second. The number of exposure intervals delivered per lesion was chosen according to the size of papules. The data was analyzed using SPSS 15.0, and p-value of p<0.05 had been used. Results: Relationship of the treatment response and Northern tribes was found statistically relevant (p<0.05). Three and six weeks after the last session, evaluation of patients response was as following: - Excellent response in 17 patients (85%), - Very good in 3 patients (15%), - Good (0.0%), - Bad (0.0%), - No response (0.0%). Conclusions: This study proved that the use of Nd: YAG laser 1064 nm, with certain parameters could achieve excellent or very good results in all patients.
The Effect of Q-Switched Nd:YAG 1064?nm/532?nm Laser in the Treatment of Onychomycosis In Vivo  [PDF]
Kostas Kalokasidis,Meltem Onder,Myrto-Georgia Trakatelli,Bertrand Richert,Klaus Fritz
Dermatology Research and Practice , 2013, DOI: 10.1155/2013/379725
Abstract: In this prospective clinical study, the Q-Switched Nd:YAG 1064?nm/532?nm laser (Light Age, Inc., Somerset, NJ, USA) was used on 131 onychomycosis subjects (94 females, 37 males; ages 18 to 68 years). Mycotic cultures were taken and fungus types were detected. The laser protocol included two sessions with a one-month interval. Treatment duration was approximately 15 minutes per session and patients were observed over a 3-month time period. Laser fluencies of 14?J/cm2 were applied at 9 billionths of a second pulse duration and at 5?Hz frequency. Follow-up was performed at 3 months with mycological cultures. Before and after digital photographs were taken. Adverse effects were recorded and all participants completed “self-evaluation questionnaires” rating their level of satisfaction. All subjects were well satisfied with the treatments, there were no noticeable side effects, and no significant differences were found treating men versus women. At the 3-month follow-up 95.42% of the patients were laboratory mycologically cured of fungal infection. This clinical study demonstrates that fungal nail infections can be effectively and safely treated with Q-Switched Nd:YAG 1064?nm/532?nm laser. It can also be combined with systemic oral antifungals providing more limited treatment time. 1. Introduction Onychomycosis is defined as a fungal infection of the nail that expands slowly and if left untreated leads to complete destruction of the nail plate. Onychomycosis can be dermatophytic (99%) and/or nondermatophytic (1%) (including yeasts) infections of the nail plate. The dermatophytes Trichophyton rubrum and Trichophyton mentagrophytes are the most common causative pathogens responsible for up to 90% of all cases [1]. Onychomycosis represents about 30% of all dermatophyte infections and accounts for 18%–40% of all nail disorders. The prevalence of onychomycosis ranges between 2% and 28% of the general population and it is estimated to be significantly higher in specific populations such as in diabetes mellitus, the immunosuppressed, and elderly [2, 3]. Among the nondermatophytes, the yeast Candida albicans, Candida tropicalis, aspergillus, and other molds may be responsible. It usually represents contamination and is an emerging problem in HIV patients. Toenails are far more likely to be involved than fingernails. Initially solitary nails are involved; later, many may be infected, but often one or more can stay disease-free. Onychomycosis has no tendency for spontaneous remission and should be considered as a problem with serious medical, social, and emotional
Pulsed 1064 nm Nd-YAG Laser Deposition of Titanium on Silicon in a Nitrogen Environment  [cached]
Jose Omar Amistoso,Edgardo Pabit,Marilyn Hui,Wilson Garcia
Science Diliman , 1999,
Abstract: Pulsed laser deposition (PLD) technique was demonstrated for the deposition of titanium nitride (TiN) thin films on Si (100) substrates. A 1064 nm pulsed Nd-YAG laser is focused on a titanium (99.5%) target in a nitrogen environment to generate the atomic flux needed for the film deposition. Spectroscopic analysis of the plasma emission indicates the presence of atomic titanium and nitrogen, which are the precursors of TiN. Images of the films grown at different laser pulse energies show an increase in the number and size of deposited droplets and clusters with increasing laser pulse energy. A decrease in cluster and droplet size is also observed, with an increase in substrate temperature. EDS data show an increase in the titanium peak relative to the silicon as the ambient nitrogen pressure is decreased. An increase in deposition time was found to result in large clusters and irregularly shaped structures on the substrate. Post-deposition annealing of the samples enhanced the crystallinity of the film.
Effect of 0.3-Millisecond Multi-Pulsed 1064-nm Nd:YAG Laser in Patients with Postherpetic Neuralgia  [PDF]
Koji Itai, Ayumi Korekawa, Kayo Jin, Takayuki Aizu, Akiko Rokunohe, Chihiro Hagiwara, Katsumi Hanada, Daisuke Sawamura
Journal of Cosmetics, Dermatological Sciences and Applications (JCDSA) , 2012, DOI: 10.4236/jcdsa.2012.21003
Abstract: Postherpetic neuralgia (PHN) is the most common complication following acute varicella zoster virus infection. PHN is associated with chronic severe pain and is resistant to conservative management treatments. The purpose of this study was to evaluate the effect of 0.3-millisecond multi-pulsed 1064-nm Nd:YAG laser treatment on PHN. Five subjects were treated with 2 - 3 sessions at 2-week interval. After the treatments, reduced visual analog scale (VAS) scores were noted in all patients. Treatments showed no adverse or intolerant effects and all patients felt warmth and comfort during the therapy. We first reported treating PHN patients using 0.3-millisecond multi-pulsed 1064-nm laser Nd:YAG. The results showed remarkable improvements in pain. This laser treatment could be an alternative choice for PHN patients with intractable neuralgia.
Two-hertz-linewidth Nd:YAG lasers at 1064nm stabilized to vertically mounted ultra-stable cavities

Jiang Yan-Yi,Bi Zhi-Yi,Xu Xin-Ye,Ma Long-Sheng,

中国物理 B , 2008,
Abstract: Two Nd:YAG lasers operating at 1064\,nm are separately servo-locked to two vertically mounted ultra-stable cavities. The optical heterodyne beat between two cavity-stabilized lasers shows that the linewidth of each laser reaches 2\,Hz and the average frequency drift reduces to less than 1\,Hz/s.
All-Solid-State Nd:YAG Laser Operating at 1064nm and 1319nm under 885nm Thermally Boosted Pumping

DING Xin,CHEN Na,SHENG Quan,YU Xuan-Yi,XU Xiao-Yan,WEN Wu-Qi,ZHOU Rui,WANG Peng,YAO Jian-Quan,

中国物理快报 , 2009,
Abstract: We report a high-efficiency Nd:YAG laser operating at 1064nm and 1319nm, respectively, thermally boosted pumped by an all-solid-state Q-switched Ti:sapphire laser at 885nm. The maximum outputs of 825.4mW and 459.4mW, at 1064nm and 1319nm respectively, are obtained in a 8-mm-thick 1.1at.% Nd:YAG crystal with 2.1W of incident pump power at 885nm, leading to a high slope efficiency with respect to the absorbed pump power of 68.5% and 42.0%. Comparative results obtained by the traditional pumping at 808nm are presented, showing that the slope efficiency and the threshold with respect to the absorbed pump power at 1064nm under the 885nm pumping are 12.2% higher and 7.3% lower than those of 808nm pumping. At 1319nm, the slope efficiency and the threshold with respect to the absorbed pump power under 885nm pumping are 9.9% higher and 3.5% lower than those of 808nm pumping. The heat generation operating at 1064nm and 1319nm is reduced by 19.8% and 11.1%, respectively.
ld泵浦nd:yag946nm/1064nm双波长运转及腔内和频  [PDF]
强激光与粒子束 , 2005,
Abstract: ?用国产半导体激光二极管(ld)端面泵浦nd:yag晶体,通过优化激光谐振腔反射膜系,调节1064nm谱线的线性损耗以达到与弱谱线946nm的增益匹配,在室温下实现1064nm和946nm双波长连续运转,并通过i类临界相位匹配lbo晶体腔内和频在国内首次实现500.8nm青色激光连续输出。当泵浦注入功率为1.4w时和频青色激光最大输出达20mw,光-光转换效率为1.4%,功率稳定性24h内优于±3%。
Silicon surface microstructures created by 1064 nm Nd: YAG nanosecond laser

Yang Hong-Dao,Li Xiao-Hong,Li Guo-Qiang,Yuan Chun-Hua,Tang Duo-Chang,Xu Qin,Qiu Rong,Wang Jun-Bo,

物理学报 , 2011,
Abstract: 利用Nd:YAG纳秒激光(波长为1064nm)在不同气氛(空气、N2,真空)中对单晶硅进行累积脉冲辐照,研究了表面微结构的演化情况.在激光辐照的初始阶段,与532和355nm纳秒脉冲激光在硅表面诱导出波纹结构不同,1064nm脉冲激光诱导出了微孔结构和折断线结构,并且硅的晶面取向不同,相应的折断线结构也不同.对于Si(111)面,两条折线交角为120°或60°,形成网状;而对于Si(100)面,两条折断线正交,从而将表面分成了15—20μm的矩形块.结果表明,微孔结构的生长过程主要与相爆炸有关,而折断线的形成主要是热应力作用的结果.不同气氛对微结构形成的影响表明,刻蚀率和生长率与微结构的形成有密切的关系.
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