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1.
The influence of spatial saturation modulation of both the amplifier and absorber in a laser with a Fabry-Perot resonator, and of the associated Bragg-reflection, on the frequency-dependent losses necessary for single-frequency operation, as well as on the frequency synchronization of three modes, has been examined. Conditions for mode selection and mode synchronization are given. To achieve single-frequency operation in a laser with a Fabry-Perot resonator the loss difference between the mode to be selected and modes to be quenched has to be proportional to the Bragg losses of the selected mode suffered by its self-induced grating. The proportionality factor depends on the length and position of the amplifier in the cavity. In the case of a short amplifier and a short absorber inside the resonator, the discussion of conditions for synchronization of three modes shows that the synchronization regime is also determined by the position of the absorber. 相似文献
2.
Arvidsson M 《Optics letters》2001,26(4):196-198
Pulse-timing effects in the far field of a passively Q -switched microchip laser that are caused by the changing cavity mode during pulse emission are described. Measurements are performed on a passively Q -switched Nd:YAG laser that produces 3-ns pulses, and delays in pulse arrival times of up to ~270 ps are observed between the center and the off-axis position. The measured data agree well with a simple analytical model. Pulse delays of this order are important, for instance, in high-precision range-finding applications. 相似文献
3.
We demonstrate a passively Q -switched diode-pumped 1.34- microm Nd:YVO(4) microchip laser. We achieved single-frequency, 230-ps pulses by using an InGaAsP semiconductor saturable-absorber mirror. We can vary the pulse width and the repetition rate from 230ps to 12ns and from 30 kHz to 4 MHz, respectively, by changing the design parameters of the saturable absorber, the thickness of the crystal, and the pump power. 相似文献
4.
High-power diode-pumped Q-switched and mode-locked Nd:YVO(4) laser with a Cr(4+):YAG saturable absorber 总被引:3,自引:0,他引:3
We demonstrate a high-power passively Q -switched and mode-locked Nd:YVO(4) laser with a Cr(4+):YAG saturable absorber. 2.7 W of average power with an 18-kHz Q -switched repetition rate was generated at a 12.5-W pump power. The peak power of a single pulse near the maximum of the Q -switched envelope was greater than 100 kW. 相似文献
5.
胡宗福 《中国光学快报(英文版)》2009,7(7):608-610
A longer laser resonator length is benefit for laser linewidth, but harmful for single-frequency operation. A novel way is suggested to narrow the bandwidth of a Fabry-Perot (FP) cavity through increasing the derivative of one round-trip phase shift with respect to the frequency. It can be implemented by replacing one of two FP mirrors with a Gires-Tournois etalon (GTE), called FPCT, as a dispersion element. FPGT resonator has additional axial modes due to the GTE reflection phase shift. Theoretical analyses show that the bandwidth of additional axial modes can be 1% of that of a conventional FP cavity. A distributed feedback (DFB) laser diode can employ FPGT resonator to achieve ultra-narrow linewidth laser. It is shown that the effect of refractivity fluctuation in the gain medium on the linewidth is little, and kilohertz linewidth is achievable for such a device. 相似文献
6.
研究了激光二极管抽运的可调频差的双频固体激光器,激光增益介质为2mm厚的1at%掺杂Nd:YAG薄片.对谐振腔产生稳定双频激光的条件作了分析,用琼斯矩阵计算了谐振腔内各处电场矢量的偏振态,证明了双频激光两个电场矢量偏振态之间总是正交的.两个偏振激光频率间隔由改变λ/4波片快轴之间的夹角实现调谐.实验中使用腔内标准具实现单频运转,然后插入双λ/4波片使单纵模激光频率分裂,实现了激光器的双频输出.实验中得到双频激光稳定运转时频差的上限约为1.3GHz;由于强模竞争现象的存在,实验中所观察到的频差下限为50MHz. 100MHz拍频时得到的双频激光输出功率为85mW.
关键词:
激光技术
固体激光器
双频激光 相似文献
7.
J. Kauppinen 《Applied physics. B, Lasers and optics》1981,26(3):193-195
A simple method for single-frequency operation and stabilization of a low power He–Ne laser has been described and used. With a proper resonator length very weak sideband modes on each side of the strong mode produce a feedback signal to a piezoelectric pusher which controls the resonator length. The long-term frequency stability was estimated to be about ±10 MHz. 相似文献
8.
A compact high-power yellow pulsed laser has been demonstrated by use of intracavity sum-frequency mixing in a diode-end-pumped Q -switched Nd:YVO(4) dual-wavelength laser. A three-mirror configuration forming two separate laser cavities is used to optimize the gain match for simultaneous dual-wavelength emission in Q -switched operation. Under the optimum cavity-length condition, the highest yellow average power is 340 mW and the peak power is 2 kW, obtained at 12.5 W of pump power. 相似文献
9.
10.
We implemented two different experimental setups to probe directly the nonlinear coupling between modes in microchip lasers. We show that, remarkably, the results can be interpreted by use of Lamb's coupling constant. In an Er, Yb:glass microchip laser, we measured C(12) = 0.80 between longitudinal modes and C(xy) = 0.95 between orthogonally linearly polarized eigenstates. The high values obtained give some physical insight into the single-frequency operation of such lasers. 相似文献
11.
Intracavity control of a 200-W continuous-wave Nd:YAG laser by a micromachined deformable mirror 总被引:1,自引:0,他引:1
A silicon micromachined membrane deformable mirror with a diameter of 10 mm, reflectivity of better than 99.8%, and a surface deflection range of 3mum has been used for intracavity control of an industrial 200-W cw Nd:YAG laser. When it was placed in the resonator, the mirror demonstrated continuous (more than 40-h) stable operation under an ~550-W cw optical load, with beam diameters in the range 3-6 mm. Periodic modulation of the curvature of the deformable mirror with a frequency of 250 Hz produced quick switching between stable and unstable resonator configurations, which resulted in pulse-period Q -switched generation with average power in the range 50-200 W, modulation depth from 95% to 10%, and an M(2) parameter of 6.5 to 30. 相似文献
12.
Xinrui Xu Rongwei Fan Renpeng Yan Yufei Ma Zhiwei Dong Xudong Li Deying Chen 《Journal of Russian Laser Research》2017,38(5):475-481
We propose a linearly frequency-tuning single-frequency Nd:YVO4 laser. We achieve a single-frequency tuning operation with a tuning range of 6.3 GHz and a maximum power of 0.5 W at 1,064 nm by tilting a thin coated etalon and changing the voltage applied to an RTP crystal in a synchronous way. The laser is linearly tuned with a standard frequency variation of ~190 MHz. We estimate the average tuning speed to be 0.81 GHz/s. The tuning range obtained is more than three times the longitudinal mode spacing of the laser resonator. 相似文献
13.
ZHAO Shengzhi WANG Qingpu ZHANG Xingyu WANG Songtao ZHAO Lu 《Chinese Journal of Lasers》1996,5(5):397-402
IntracavityFrequencyDoublingofaNewLow-thresholdHigh-efficiencyCrystalNd:Sr_5(VO_4)_3FZHAOShengzhi;WANGQingpu;ZHANGXingyu;WANG... 相似文献
14.
Bäder U Meyn JP Bartschke J Weber T Borsutzky A Wallenstein R Batchko RG Fejer MM Byer RL 《Optics letters》1999,24(22):1608-1610
We report an efficient, visible, nanosecond optical parametric generator of periodically poled lithium niobate pumped at 532 nm by a frequency-doubled, diode-pumped, passively Q -switched, single-mode Nd:YAG laser with 90-muJ pulse energy. The signal radiation is tunable from 637 to 593 nm. The maximum signal-conversion efficiency is 23%. Optical parametric amplification of a He-Ne laser at 632.8 nm is also studied. 相似文献
15.
We present a diode-pumped, double-clad Yb:YAG waveguide laser that contains an integrated section of a Cr(4+): YAG saturable absorber for passive Q switching. Using two 4-W polarization-coupled, broad-striped diode-pumped lasers, we obtained 30-microJ pulses of 1.6-ns duration at repetition rates of as much as 77 kHz. The slope efficiency was ~50% with respect to absorbed pump power, with a maximum output average power of 2.3 W and a peak power of ~18 kW . The output beam was single lobed, with M(2) values as great as 1.5x1.3 . We also demonstrate a passively Q -switched Nd:YAG waveguide laser of similar design, operating at 1.064 microm and 946 nm. 相似文献
16.
Passively Q-switched Nd:YAG ring lasers with high average output power in single-frequency operation 总被引:1,自引:0,他引:1
Applying Cr(4+):YAG saturable absorbers, we demonstrate efficient passively Q -switched operation of diode-pumped Nd:YAG lasers with a maximum average output power of more than 800 mW. Pulse durations below 3 ns, energies of 70 muJ, and peak powers of 30 kW are observed with kilohertz repetition rates. Single-frequency operation is accomplished for all output powers by a nonplanar ring geometry. 相似文献
17.
Laroche M Chardon AM Nilsson J Shepherd DP Clarkson WA Girard S Moncorgé R 《Optics letters》2002,27(22):1980-1982
Efficient repetitive passive Q switching of a cladding-pumped Er-Yb fiber laser has been demonstrated by use of an external-cavity configuration containing a Co(2+): ZnS crystal as a saturable absorber. Energies of as much as 60muJ in pulses of durations as short as 3.5 ns (FWHM), corresponding to a peak power of >10kW, have been generated, and the maximum slope efficiency with respect to the absorbed pump power was 13%. Using a bulk diffraction grating in the Littrow configuration to provide wavelength-selective feedback, we tuned the passively Q -switched fiber laser over 31 nm from 1532 to 1563 nm. The prospects for further improvement in performance are discussed. 相似文献
18.
There is a need for an intense, unmodulated single-frequency stabilized laser light that guarantees absolute optical frequency in a rapid laser calibration or an ultra-high resolution interferometer. To obtain such a light, we developed a new laser system that uses an intermittent frequency offset lock of a symmetric three-mode stabilized He-Ne laser to an iodine stabilized He-Ne laser. The proposed laser system provides two operational modes: (1) independent and (2) slave mode. In the independent mode, frequency of the three-mode laser is stabilized via control of frequency difference between two intermode beats. The resultant output is a single longitudinal mode light of maximum intensity that locates at the top of the gain curve. Frequency instability of 8X10-12 (at a sampling time of 100 s) which is better than conventional stabilized lasers is attained in the independent mode. Slow optical frequency drift during the independent mode is periodically corrected by the offset lock to the iodine stabilized laser (slave mode), resulting in accurate reset of the frequency drift. After reset of the frequency deviation, the three-mode laser is again operated in the independent mode. Due to such intermittent offset lock, duty factor of the iodine stabilized laser was reduced to a few % of continuous operation. 相似文献
19.
Gerald T. Moore 《Optics Communications》1984,52(1):46-51
The small-signal regime of the free-electron laser is analyzed for single-frequency, uniform-wiggler operation, taking diffraction into account. Exponentially growing modes are found with profiles independent of the longitudinal coordinate. Maximum gain occurs for a positive value of the energy detuning, though the gain on resonance is nearly maximal. If the current transverse distribution is uniform and sharp-edged, analytic solutions are obtained in terms of Bessel and Hankel functions with complex arguments. Positive energy detuning broadens the laser modes, while negative detuning concentrates them within the electron beam. 相似文献
20.
3+ :Ho3+:YAG laser is operated in active mirror configuration. This laser is characterised by a rather thin crystal (3 mm thickness
in our experiment) and a very short resonator (about 3.2 mm). Therefore this laser is well suited for operation in a single
longitudinal mode. Single-frequency operation is demonstrated with and without an intracavity etalon. It is further shown
that single-frequency emission is reached with a stable cw emission. With a slight detuning of the outcoupling mirror, spiking
can be achieved, resulting in an emission on different lines. The assignment of the observed laser lines to the known transitions
between Stark sublevels of the 5I7 and the 5I8 level is discussed and compared with predictions in the literature.
Received: 2 December 1997 相似文献