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961.
Narrow linewidth continuous-wave Tm:YLF laser at room temperature with a Volume Bragg grating and double Fabry-Perot etalons
by using the end-pumping configuration was presented. The Tm:YLF laser operates at 1907.3 nm with FWHM of approximately 60
pm. We achieved the maximum output power of 1.92 W when the incident pump power of 13.9 W, corresponding to the optical-to-optical
conversion efficiency of 13.8% and slope efficiency of 16.4%. 相似文献
962.
Resurfacing using a fractional CO2 laser shows an important promise in the therapy on photoaged skin. The present study investigated that fractional CO2 laser with a special sequential scanned manner induced the collagen remodelling in murine dermis. The results showed that
laser resulted in the improvement of elasticity and histology in the murine dermis, meaning laser efficacy depends on both
of the collagen formation and organization. We further investigated the relations between skin elasticity and type I, and
type III collagen. These data demonstrated that laser could significantly lead to the collagen remodelling in murine dermis
and induce neocollagenisis as a mode of resurfacing. 相似文献
963.
Interaction of two identical excitable spiral waves in a bilayer system is studied. We find that the two spiral waves can be completely synchronized if the coupling strength is sufficiently large. Prior to the complete synchronization, we find a new type of weak synchronization between the two coupled systems, i.e., the spiral wave of the driven system has the same geometric shape as the spiral wave of the driving system but with a much lower amplitude. This general behavior, called projective synchronization of two spiral waves, is similar to projective synchronization of two coupled nonlinear oscillators, which has been extensively studied before. The underlying mechanism is uncovered by the study of pulse collision in one-dimensional systems. 相似文献
964.
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
965.
J. Q. Di X. D. Xu D. Z. Li D. H. Zhou F. Wu Z. W. Zhao J. Xu D. Y. Tang 《Laser Physics》2011,21(10):1742-1744
Three mixed crystals, Nd:GdYAG, Nd:LuYAG, and Nd:GdLuAG, were grown by Czochralski method. We report the continuous-wave (CW)
Nd:GdYAG, Nd:LuYAG, and Nd:GdLuAG laser operation under laser diode pumping. The maximum output powers are 4.11, 5.31, and
7.47 W, with slope efficiency of 73.0, 55.3, and 57.1%, respectively. With replacing Lu3+ or Y3+ ions with large Gd3+ ions, the pump efficiency increases. 相似文献
966.
Diode pumped operation of 1 mm Tm,Ho:YAP microchip laser 总被引:1,自引:0,他引:1
A single-longitudinal-mode (SLM) operation of a c-cut 1 mm Tm(5%), Ho(0.3%):YAP micro-chip laser pumped by a fiber-coupled
diode-laser was reported. Under cryogenic temperature, the output power of 216 mW was obtained under the incident power of
2230 mW, corresponding to the slope efficiency was 13.6%. As much as 133 mW output and slope efficiency of 4.9% was obtained
under the pump power of 3000 mW at 291 K. In addition, a maximum SLM output power of 30 mW at wavelength of 2130.56 nm is
demonstrated under 77 K. 相似文献
967.
A passively Q-switched waveguide laser, to our knowledge, has been firstly demonstrated in Nd: YVO4 crystal formed by 3 MeV Si+ ion implantation at a dose of 1 × 1015 ions/cm2 at room temperature, in which GaAs was used as saturable absorber. The dependences of the average output power, pulse width,
pulse repetition rate on absorbed pump power have been measured at different output plane mirror transmissions. At an absorbed
pump power of 78.8 mW and output transmission of 20%, the shortest pulse width of 3.88 ns was obtained, corresponding to the
peak power and single pulse energy of 212 W and 0.82 μJ, respectively. The threshold pump power was as low as 40 mW, and the
slope efficiency was about 64.5% when the absorbed pump power was lower than 70 mW. 相似文献
968.
B. Ibarra-Escamilla O. Pottiez R. Zhou Q. Zhan P. E. Powers E. A. Kuzin J. W. Haus 《Laser Physics》2011,21(11):1936-1940
We experimentally demonstrated a stable, wavelength-tunable fiber laser using a polarization-maintaining, double-clad Er:Yb
doped fiber amplifier in the cavity. The output wavelength is tunable over the range from 1535 to 1567 nm using a fixed grating
and the dichroic mirror placed on a rotational mount; under rotation of the dichroic mirror the tuning ratio of 50 nm/deg
was found. We studied the wavelength tuning range dependence on the amplifier fiber length and achieved a maximal output power
of 850 mW. This configuration can be Q-switched for high peak power and its narrow bandwidth is suitable for nonlinear optics
applications, such as parametric teraherthz generator. 相似文献
969.
A Q-switched mode-locking femtosecond all-fiber laser based on a 2 cm long homemade Er3+/Yb3+ codoped phosphate glass fiber has been reported. By using the nonlinear polarization evolution technique, a nearly 100% modulation
depth of mode-locking pulse train is achieved. At a pump power of 410 mW, the energy of each Q-switched envelope, whose width
is about 220 μs, is 10 μJ, while the duration of mode-locking pulse within the Q-switched envelope is 318-fs. 相似文献
970.
Z. Q. Hui 《Laser Physics》2011,21(7):1219-1229
All-optical single-to-dual channel format conversion from NRZ to RZ at 10 Gbit/s using cross phase modulation (XPM) in dispersion
flattened highly nonlinear photonic crystal fiber (DF-HNL-PCF) is demonstrated. Format conversion with dual channels signal
multicasting function is achieved by filtering simultaneously the blue- and red-chirped components of broadened optical spectrum
induced by XPM between NRZ signal and clock light. Moreover, the wavelength tunability and dynamics characteristics of proposed
format converter are also exploited experimentally by using NRZ signal light with different central wavelength and varying
input power. Our results show that a wide wavelength operation range of 21.2 nm, extinction ratio (ER) and Q factor of over
10.9 dB and 6.1 are obtained. Furthermore, the influence of central wavelength offset of optical bandpass filter on converted
RZ signal quality is investigated. The proposed scheme is simple, robust, and transparent to bit rate, which makes it very
potential for application in future photonic networks. 相似文献