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991.
A novel compact supercontinuum (SC) source using the single mode photonic crystal fibers (PCF) pumped with an all fiber MOPA
fiber laser is demonstrated experimentally. A bandwidth of 700 nm is achieved by operating the pumping fiber laser at a wavelength
of 1064 nm, pulse duration of 10 ns, repetition rate of 50 kHz and peak power of 1 kW. The SC generation is initiated through
modulation instability (MI) which breakups the nanosecond pump pulses into picosecond or femtosecond pulses, and further broadened
through nonlinear effects of PCF. 相似文献
992.
B. Z. Li C. G. Sun A. F. Zang X. H. Zhang M. Zhao J. B. Wang G. Y. Jin 《Laser Physics》2011,21(6):988-990
We describe the output performances of the 1048 nm transition in Yb:YAG under in-band pumping with diode laser at the 968 nm wavelength. An end-pumped Yb:YAG crystal yielded 787 mW of continuous-wave (CW) output power for 9.1 W of absorbed pump power. Furthermore, 104 mW 524 nm green light was acquired by frequency doubling. Comparative results obtained for the pump with diode laser at 940 nm are given in order to prove the advantages of the in-band pumping. 相似文献
993.
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
994.
Efficient and compact green-yellow laser output at 545 nm is generated by intracavity frequency doubling of a continuous-wave
(CW) diode-pumped Nd:LuVO4 laser at 1089 nm under the condition of suppressing the higher gain transition near 1066 nm. With 18.7 W of diode pump power
and the frequency-doubling crystal KTiOPO4(KTP), as high as 2.3 W of CW output power at 545 nm is achieved, corresponding to an optical-to-optical conversion efficiency
of 12.3%; the output power stability over 4 h is better than 5.4%. 相似文献
995.
A high stability all-fiber LD-clad-pumped Tm3+-doped fiber laser was reported. The fiber laser had the ultra-narrow linewidth 50 pm at 1.948 μm with the maximal output
power of 12.8 W. The slope efficiency was 28.9%, and threshold was 5.7 W. The double-clad Tm3+-doped fiber core was multi-mode, which had a demission of 25/250 μm with the core NA of 0.1 and inner-clad NA of 0.46. The
high reflectivity coupler FBG was directly written into the single-mode passive photosensitive optical fiber core, which had
a core diameter of 15 μm and NA of 0.1. The cavity was build-up by the high reflectivity FBG and the output fiber end Fresnel
reflectivity. 相似文献
996.
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
997.
Solid-state dye samples based on modified polymethyl methacrylate with methanol (MPMMA) doped with pyrromethene 567 (PM567)
were first prepared. The effects of volume percentage of methanol on the laser performances of the samples, including spectra
properties, slope efficiency and photostability were studied. The highest slope efficiency 66.39% was obtained in the sample
(MMA:methanol = 16:4). Pumping the samples at a repetition rate of 5 Hz with a pulse energy as high as 100 mJ (the fluence
was 0.26 J/cm2), the output energy dropped to half of its initial value after approximate 156720 shots and the corresponding normalized
photostability reached 101.86 GJ/mol in the sample (MMA:methanol = 17:3). Our results indicate that it can obtain a high slope
efficiency and good photostability for a solid-state dye laser using MPMMA as solid hosts. 相似文献
998.
A widely tunable narrow linewidth compact erbium-doped all-fiber ring laser with 104 nm tuning range was reported. An all-fiber
Fabry-Perot filter (FFP-TF) was used to realize the laser tuning output, and the wavelength at constant voltage had high time
stability. With the 8 m length erbium-doped fiber as gain medium, we realized widely tunable laser from 1513 to 1617 nm with
the linewidth less than 40 pm at any wavelength. Pumped by the 976 nm laser diode, the fiber laser worked with slope efficiency
of above 10% and threshold of less than 21 mW. 相似文献
999.
A low-noise, ultra-short linear-cavity distributed feedback fiber laser (DFB-FL) with extremely narrow linewidth is presented.
The FL has a total length of 17 mm, which is, to our knowledge, the shortest DFB-FL being reported. It has a measured linewidth
of merely 250 Hz without active stabilization. It has a polarization beat frequency of 101 MHz, which is several times lower
than that of most FLs. The relaxation oscillation frequency and relative peak are 110 kHz and −76.5 dB/Hz, respectively. The
FL exhibited low-noise characteristics, with an intensity noise of −107 dB/Hz at 1 MHz. Due to low dopant concentration of
the EDF and low splice loss with ordinary single-mode fibers, the net insertion loss amounts to only 0.45 dB. Such low pump
power loss greatly enhances the capability of multiplexing a large number of FL sensors. Thus, these ultra-short DFB-FLs open
up new opportunities for the development of compact-sized point sensor array systems for large-scale high sensitivity sensing
applications. 相似文献
1000.
The quasi-three-level 908-nm continuous-wave laser emission under direct diode laser pumping at 880 nm into emitting level
4
F
3/2 of Nd:YLF have been demonstrated. An end-pumped Nd:YLF crystal yielded 4.7 W of output power for 11.8 W of absorbed pump
power. The slope efficiency with respect to the absorbed pump power was 43.3%. Comparative results obtained for the pump with
diode laser at 808 nm, into the highly-absorbing 4
F
5/2 level, are given in order to prove the advantages of the 880-nm wavelength pumping. 相似文献