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991.
J.-H. Yuan X.-Z. Sang C.-X. Yu L. Rao Y. Han G.-Y. Zhou S.-G. Li L.-T. Hou 《Applied physics. B, Lasers and optics》2011,105(4):685-688
Using the photonic crystal fiber (PCF) with the zero dispersion wavelength of 848 nm for the fundamental mode, the efficient
anti-Stokes signal generations from 645 to 543 nm are realized by pumping in the normal dispersion region. When the pump average
power increases from 200 to 500 mW, the output power of the anti-Stokes signal increases 8.46 times, the power ratio of the
anti-Stokes signal at 543 nm to the residual pump is calculated as 22.6:1, and the conversion efficiency η in the experiment can be up to 46%. Moreover, good optical beam quality of the anti-Stokes signal can be achieved. 相似文献
992.
X. F. Yang D. Y. Shen T. Zhao H. Chen J. Zhou J. Li H. M. Kou Y. B. Pan 《Laser Physics》2011,21(6):1013-1016
We report on a high power polycrystalline Er:YAG ceramic laser in-band pumped by a cladding-pumped Er, Yb fiber laser wavelength
locked at 1532 nm with a volume Bragg grating. Using 1.0 at % Er3+-doped ceramic as the gain medium and an output coupler of 10% transmission, the laser had a threshold pump power of ∼1.5
W and generated 11 W of continuous-wave output at 1645 nm for 23.3 W of incident pump power at 1532 nm, corresponding to a
slope efficiency with respect to incident pump power of 51%. 相似文献
993.
Diode-pumped Pr<Superscript>3+</Superscript>:YAlO<Subscript>3</Subscript>/LBO violet laser at 374 nm
We report a diode-pumped Pr3+:YAlO3 laser emitting at 747 nm. A power of 232 mW at 747 nm has been achieved in continuous-wave operation with a diode emitting
2 W at 448 nm. Furthermore, intracavity second-harmonic generation in continuous-wave mode has also been demonstrated with
a power of 52 mW at 374 nm by using a LBO nonlinear crystal. The fluctuation of the violet output power was better than 2.3%.
The beam quality M
2 value is 2.2. 相似文献
994.
A simple scheme for a switchable multi-wavelength erbium-doped fiber (EDF) ring laser is investigated by using a single stage
of a Sagnac loop mirror. The multiple lasing outputs are obtained and switched readily by controlling the state of polarization
(SOP). Since the transmission characteristics of the Sagnac loop mirror in terms of peak wavelengths and peak powers strongly
depend on the SOP, the switching performance of the proposed multi-wavelength EDF laser can be effectively obtained. The proposed
multi-wavelength EDF laser has versatile lasing outputs in states of a single-, dual-, triple-, and quadruple-wavelength oscillations.
The multiple outputs are effectively switchable by adjusting the SOP. 相似文献
995.
X. Ni G. V. Naik A. V. Kildishev Y. Barnakov A. Boltasseva V. M. Shalaev 《Applied physics. B, Lasers and optics》2011,103(3):553-558
Spontaneous emission patterns of electric and magnetic dipoles on different metallic surfaces and a hyperbolic metamaterial
(HMM) surface were simulated using the dyadic Green’s function technique. The theoretical approach was verified by experimental
results obtained by measuring angular-dependent emission spectra of europium ions on top of different films. The results show
the modified behavior of electric and magnetic dipoles on metallic and HMM surfaces. The results of numerical calculations
agree well with experimental data. 相似文献
996.
The efficient oscillation of LiF:F2− color center laser pumped by a compact LD-pumped Nd:YVO4 acousto optically Q-switched laser with 30 kHz pulse repetition rate was demonstrated. The broadband oscillation with 75
μJ pulse energy and 37 kW peak power with the slope efficiency 20% was obtained. The average output power as high as 230 mW
was reached. The narrow line tunable from 1.10 to 1.29 μm laser radiation with 10% conversion efficiency in the maximum of
the tuning curve was achieved under pumping with 1.6 W average pump power. 相似文献
997.
We report a diode-pumped Nd:LuVO4 laser emitting at 1076 nm, based on the 4
F
3/2−4
I
11/2 transition, generally used for a 1066 nm emission. A power of 689 mW at 1076 nm has been achieved in continuous-wave (CW)
operation with a fiber-coupled laser diode emitting 17.8 W at 809 nm. Intracavity second-harmonic generation (SHG) in CW mode
has also been demonstrated with a power of 105 mW at 538 nm by using a LiB3O5 (LBO) nonlinear crystal. 相似文献
998.
Using the vertical evaporation technique we fabricated saturable absorbers by transferring the double-wall carbon nanotubes
(DWCNT) onto a hydrophilic quartz substrate. The fast recovery time and the saturation intensity of the absorber were measured
to be 228 fs and 130 μJ/cm2, respectively, at 1060 nm. The modulation depth of the absorber was about 3.7%. Passive mode-locked Nd:GdVO4 laser was demonstrated. The continuous wave mode-locked pulses pulse duration is 5.6 ps and the largest average output power
is 1.2 W at the pump power of 9.5 W. To the best of our knowledge, this is the first demonstration of high power continuous
wave mode locking laser with DWCNT absorber. 相似文献
999.
The infrared and visible cooperative emissions of ytterbium ions are studied in Yb-doped NdVO4 single crystals. The absorption of optical phonons allows the emissions at room temperature when a Nd:YAG laser is used. Low temperature emissions are observed due to the Nd3+→Yb3+ energy transfer following an argon ion laser excitation of the Nd3+ ions. Analysis of the cooperative emission at low doping concentration (1%) indicates that it is generated by distant pair forming Yb3+ ions while at high doping concentration (≥ 5%) close ions magnetically coupled and superexchange mechanisms prevail in the emitting process. 相似文献
1000.
The attenuation of the transverse vibration of a plate, subjected to a harmonic force, is studied. This goal can be achieved by using an active dynamic absorber. The active absorber is made of a pair of piezoelectric sheets, attached to both sides of the plate, and closed electric circuits. One piece of the piezoelectric material provides a sensor for detecting the motion of the plate. Another piece serves as an active dynamic absorber. The equations of motion of the composite plate, including the plate and the piezoelectric material, and the circuit equations of the sensor and the absorber are derived. The displacements of the plate and the currents in the circuits are calculated. The active absorber can successfully attenuate the vibration. The numerical results show that the proposed active absorber can offer more reduction than that using a passive absorber while the absorber is designed to suppress the resonance of a particular vibration mode. Moreover, the active absorber can also reduce the displacements corresponding to other uncontrolled modes. The effects of altering various parameters of the active absorber are studied and discussed. 相似文献