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971.
In this paper, we report two crystals Tm:YLF laser pumped by a fiber coupled diode laser with total power of 180 W at 792
nm. When the incident power reached up to 117.0 and 37.3 W of the emission wave-length at 1.91 μm was achieved. Through linear
fit, the corresponding slope efficiency of 38.5%, optical-to-optical conversion efficiency of 31.9% and the beam quality factor
of M
2 ∼ 1.1 were obtained, indicating nearly diffraction limited beam propagation. To our best knowledge, this is the best beam
quality among the reported paper results under the similar experiments. 相似文献
972.
A diode end-pumped single-frequency Tm,Ho:YAP laser at room temperature was reported. We obtain a single frequency Tm,Ho:YAP
laser of up to 31 mW with Fabry-Perot etalons in the cavity at 2130.8 nm. The optical conversion efficiency is 1.0% and the
slope efficiency is 6.3%. The measured full width at half maximum (FWHM) is approximately 65 pm. The single-longitudinal-mode
(SLM) laser can be used as a seed laser for coherent wind measurements and differential absorption LIDAR systems. 相似文献
973.
B. Q. Yao F. Chen C. T. Wu Q. Wang G. Li C. H. Zhang Y. Z. Wang Y. L. Ju 《Laser Physics》2011,21(3):468-471
In this paper, we presented experimental results concerning on the laser characteristics of two microchip lasers emitting
in the 2 μm range, Tm:Ho:YVO4 microchip laser and Tm:Ho:GdVO4 microchip laser. At a heat sink temperature of 283 K, the maximum output power of Tm:Ho:YVO4 laser and Tm:Ho:GdVO4 laser is 47 and 34 mW under absorbed pump power of 912 mW, respectively. High efficiency can be achieved for both lasers
at room temperature. Nevertheless, compared with Tm:Ho:GdVO4 laser, Tm:Ho:YVO4 laser can operate on single frequency with high power easily. At the heat sink temperature of 288 K, as much as 16.5 mW of
2052.3 nm single-longitudinal-mode (SLM) laser was achieved for Tm:Ho:YVO4 laser. Under the same condition, only 8 mW of 2048.5 nm SLM laser was achieved for Tm:Ho:GdVO4 laser. 相似文献
974.
It is reported that efficient continuous-wave (CW) blue-green laser generation at 500 nm in a LBO crystal at type-I phase
matching direction performed with a Ti:sapphire laser-pumped Yb:KYW laser. With incident pump power of 8.7 W, output power
of 138 mW at 500 nm has been obtained using a 10 mm-long LBO crystal. At the output power level of 138 mW, the blue-green
output stability is better than 2.8%. The blue-green beam quality M
2 values were equal to 1.25 and 1.18 in X and Y directions, respectively. 相似文献
975.
B. Q. Yao F. Chen C. T. Wu Q. Wang G. Li C. H. Zhang Y. Z. Wang Y. L. Ju 《Laser Physics》2011,21(4):663-666
Room temperature Tm, Ho:YVO4 microchip laser operated around 2 μm was demonstrated for the first time to our knowledge. At a heat sink temperature of
283 K, a maximum output power of 47 mW was obtained by using a 0.25 mm length crystal at an absorbed pump power of 912 mW,
corresponding to a slope efficiency of 9.1%. Increasing the temperature to 288 K, as much as 16.5 mW 2052.3 nm single-longitudinal-mode
laser was achieved. The M
2 factor was measured to be 1.4. 相似文献
976.
X. L. Zhang X. Y. Zhang Q. P. Wang C. Wang H. H. Xu Y. Tang L. Li Z. J. Liu X. H. Chen S. Z. Fan Z. T. Jia X. T. Tao 《Laser Physics》2011,21(6):1047-1050
A diode-side-pumped continuous-wave Nd:GGG laser operating at dual-wavelength (1110 and 1105 nm) and single wavelength of 1110 nm is demonstrated for the first time. The maximum output power of the 1110 and 1105 nm dual-wavelength operation is 13.2 W. By adjusting the orientation of an insertion mirror, the relative intensities of the two wavelengths can be changed. Thus single wavelength operation at 1110 nm is obtained, and the output power is 9.6 W. 相似文献
977.
ZHOU Zhan YU JianShe & CHEN YuMing School of Mathematics Information Science Guangzhou University Guangzhou China 《中国科学 数学(英文版)》2011,(1)
In this paper, a periodic difference equation with saturable nonlinearity is considered. Using the linking theorem in combination with periodic approximations, we establish sufficient conditions on the nonexistence and on the existence of homoclinic solutions. Our results not only solve an open problem proposed by Pankov, but also greatly improve some existing ones even for some special cases. 相似文献
978.
We study the possibility of detecting gravitational-waves with matter-wave interferometers, where atom beams are split, deflected
and recombined totally by standing light waves. Our calculation shows that the phase shift is dominated by terms proportional
to the time derivative of the gravitational wave amplitude. Taking into account future improvements on current technologies,
it is promising to build a matter-wave interferometer detector with desired sensitivity. 相似文献
979.
Separate spatial soliton pairs in a biased series centrosymmetric photorefractive crystal circuit 总被引:1,自引:0,他引:1
It is shown theoretically that three types of separate soliton pairs: bright-bright, bright-dark, and dark-dark, can be established in a biased series circuit consisting of two centrosymmetric photorefractive crystals and the two solitons in a separate soliton pair can affect each other by the light-induced current. The effects of the intensities of soliton beams and background lights on the normalized profiles of solitons are discussed. 相似文献
980.
Tu XL Xu HS Wang M Zhang YH Litvinov YA Sun Y Schatz H Zhou XH Yuan YJ Xia JW Audi G Blaum K Du CM Geng P Hu ZG Huang WX Jin SL Liu LX Liu Y Ma X Mao RS Mei B Shuai P Sun ZY Suzuki H Tang SW Wang JS Wang ST Xiao GQ Xu X Yamaguchi T Yamaguchi Y Yan XL Yang JC Ye RP Zang YD Zhao HW Zhao TC Zhang XY Zhan WL 《Physical review letters》2011,106(11):112501
Mass excesses of short-lived A=2Z-1 nuclei (63)Ge, (65)As, (67)Se, and (71)Kr have been directly measured to be -46,921(37), -46,937(85), -46,580(67), and -46,320(141) keV, respectively. The deduced proton separation energy of -90(85) keV for (65)As shows that this nucleus is only slightly proton unbound. X-ray burst model calculations with the new mass excess of (65)As suggest that the majority of the reaction flow passes through (64)Ge via proton capture, indicating that (64)Ge is not a significant rp-process waiting point. 相似文献