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1.
Operation of a miniature Alexandrite laser pulse-pumped at 671 nm by a Q-switched, frequency-doubled, diode-pumped Nd:GdVO4 laser is reported. Average power output ∼150 mW at 765 nm with optical-to-optical slope efficiencies of 28% has been demonstrated for gain-switched operation of the Alexandrite laser at 80 kHz. Q-switched pump-pulse stacking has been used to reduce output pulse width by a factor of 6 and increase peak power by a factor of 38 over gain-switched operation. 相似文献
2.
Lasing at telecommunication wavelengths from annular resonators employing radial Bragg reflectors is demonstrated at room temperature under pulsed optical pumping. Submilliwatt pump threshold levels are observed for resonators with 0.5-1.5-wavelength-wide defects of radii 7-8 microm. The quality factors of the resonator modal fields are estimated to be of the order of a few thousand. The electromagnetic field is shown to be guided by the defect. Good agreement is found between the measured and the calculated spectra. 相似文献
3.
Liangshun Han Song Liang Can Zhang Liqiang Yu Lingjuan Zhao Hongliang Zhu Baojun Wang Chen Ji Wei Wang 《中国光学快报(英文版)》2014,12(9):91402-44
We report the fabrication of widely tunable ridge waveguide distributed Bragg reflector(DBR) lasers with InGaAsP butt-joint as grating material. The shape of the butt–joint interface is found to have significant effect on the properties of the lasers. It is shown that irregular mode jumps during wavelength tuning can be avoided by a V-shaped butt–joint interface. From the fabricated device, 23 channels with 0.8 nm spacing and greater than 35 dB side mode suppression ratios are obtained. The different tuning characteristics of the ridge waveguide and the previously reported buried ridge stripe DBR lasers are discussed. Combined with the wide tuning range and the simple structure, the ridge waveguide DBR lasers are promising for use in wavelength division multiplexing passive optical networks(WDM-PONs). 相似文献
4.
Ultraviolet short pulses from an all-solid-state Ce:LiCAF master-oscillator power-amplifier system 总被引:1,自引:0,他引:1
Sarukura N Liu Z Ohtake H Segawa Y Dubinskii MA Semashko VV Naumov AK Korableva SL Abdulsabirov RY 《Optics letters》1997,22(13):994-996
We have developed an all-solid-state master-oscillator-power-amplifier system employing Ce:LiCAF, a new degradation-free tunable ultraviolet laser medium pumped by the fourth harmonic of conventional 10-ns Q -switched Nd:YAG lasers. The low- Q , short-cavity Ce:LiCAF master oscillator produced a satellite-free 1-ns pulse under appropriate pumping-fluence control. 18% energy extraction with sufficient gain was achieved in a single-stage, confocal, double-pass amplifier. As a result, 289-nm, 1-ns, 14-mJ pulses were efficiently obtained from this simple laser system. 相似文献
5.
N. N. Koval G. A. Mesyats V. S. Skakun V. F. Tarasenko A. A. Fedenev P. M. Shchanin 《Laser Physics》2006,16(1):52-63
The lasing on the electronic transitions of xenon and neon is studied. It is demonstrated that plasma-cathode accelerators
serve as effective sources for the pumping of low-threshold lasers (W < 100 W/cm3). The laser energy in xenon at the wavelength λ = 1.73 μm is 5 J at an efficiency of 2%, and the laser energy in neon at
the wavelengths λ = 585.3 nm is 0.5 J at an efficiency of 0.3%. The repetitively pulsed mode of the xenon and neon lasers
carried out at a repetition rate of 50 Hz. The radiation energy of a wide-aperture laser with an active volume of 600 l is
100 (0) J for a wavelength of 1.73 (2.03) μm at an efficiency of 2% (1%).
Original Text ? Astro, Ltd., 2006. 相似文献
6.
Cory J. Hill Baohua Yang Rui Q. Yang 《Physica E: Low-dimensional Systems and Nanostructures》2004,20(3-4):486
Mid-IR type-II interband cascade lasers were demonstrated in pulsed mode at temperatures up to 325 K and in continuous mode up to 200 K. At 80 K, the threshold current density was 8.9 A/cm2 and a continuous wave output power of 140 mW/facet was obtained. 相似文献
7.
V. A. Lisinetskii D. N. Bus’ko R. V. Chulkov A. S. Grabchikov P. A. Apanasevich V. A. Orlovich 《Journal of Applied Spectroscopy》2008,75(2):300-307
We have studied the conditions resulting in maximum lowering of the excitation threshold for pulsed stimulated Raman (SRS)
lasers. It has been shown theoretically that in order to achieve the lowest possible values of laser radiation pulse energy
needed to excite lasing in SRS lasers, we need high reflection of the cavity mirrors and low losses at the wavelength of the
1st Stokes component, high reflection of the output mirror at the wavelength of the pump radiation, and also matching of the
confocal parameters for the exciting laser radiation and the cavity with each other and with the length of the Raman-active
medium. The experimentally achieved excitation threshold for an SRS laser based on a barium nitrate crystal was 6 μJ, which
quantitatively corresponds well to the calculation results. Lasing of up to five Stokes components simultaneously occurred.
The efficiency for conversion of the laser radiation to one component was as high as 39%.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 2, pp. 284–290, March–April, 2008. 相似文献
8.
9.
In this paper, the study of a switchable electro-optic Q-switched Nd:YAlO3 laser emitting 1080 and 1342 nm wavelength was demonstrated. The two-wavelength lasers were eradiated by a Nd:YAlO3 crystal pumped by a xenon lamp. Two KD*P Pockels cells were adopted as Q-switches. The output energy of 277.2 mJ at 1080 nm wavelength with a pulse width of 20 ns and that of 190.67 mJ at 1342 nm wavelength with a pulse width of 40 ns was obtained, respectively, in our experiment. By switching on or off the voltages applied to the Pockels cells, the operation of the two-wavelength lasers can be selected in free running mode or Q-switching mode. 相似文献
10.
Martin Ostermeyer 《Optics Communications》2007,274(2):422-428
The long fluorescence lifetime of the upper laser level of Yb:YAG seems to make it an attractive material for the realization of Q-switched pulses with large pulse energy. The consequences of the spectroscopic parameter set of Yb:YAG for the feasibility of a large pulse energy laser, which emits pulses with nanosecond duration, are addressed on the basis of a rate equation model. The rate equations are analytically solved and applied to the optical side pumping of Yb:YAG rods. The thermal population of the lower laser level and the saturation of the laser material are discussed in specific. 相似文献
11.
Liu Han Baoquan Yao Xiaoming Duan Shang Li Tongyu Dai Youlun Ju Yuezhu Wang 《中国光学快报(英文版)》2014,12(8):81401-43
In this letter, we report a Ho:YVO4 laser pumped by a 1.94-μm laser in both continuous-wave(CW)and Q-switched modes. The output performance of the Ho:YVO4 laser is compared with different output coupler transmissions. By use of the output coupler transmissions of T =30%, we obtain the maximum CW output power of 3.9 W at 2052 nm, with beam quality factor of M2=1.09 for the absorbed pump power of 12.5 W. For the Q-switched mode, we achieve maximum output energy per pulse of 0.38 mJ and the minimum pulse width of 25 ns, corresponding to the peak power of 15.2 kW. 相似文献
12.
13.
The lowest threshold current of the external-cavity semiconductor laser with fiber Bragg grating using genetic algorithms
is investigated. Effects of the external cavity length, coupling efficiency and anti-reflection coating reflectivity on static
characteristics, such as L-I curves and side mode suppression ratios (SMSR) are investigated by using multi-mode rate equation.
It is found that the reflectivity of the anti-reflection coating for low-threshold performance needs to be increased at the
cost of the stability of the fiber grating external-cavity semiconductor laser. The optimal external cavity length obtained
by genetic algorithms can be used to obtain the lowest threshold current for sacrificing a little SMSR. However, with the
decrease of AR-coating reflectivity, output powers and SMSRs are slightly dependent on the external cavity length. 相似文献
14.
Schlatter A Rudin B Zeller SC Paschotta R Spühler GJ Krainer L Haverkamp N Telle HR Keller U 《Optics letters》2005,30(12):1536-1538
We report on nearly quantum-limited timing-jitter performance of two passively mode-locked Er:Yb:glass lasers with a repetition rate of 10 GHz. The relative timing jitter of both lasers was measured to be 190 fs (100 Hz-1.56 MHz) root mean square. The remaining cavity-length fluctuations are below 7.5 pm in the 6 Hz-8 kHz frequency range, indicating the stability of a rugged miniature cavity setup. By actively controlling the cavity length we reduced the timing jitter to 26 fs (6 Hz-1.56 MHz). We also discuss the influence of cavity length on the practically achievable timing jitter. 相似文献
15.
Köhler R Tredicucci A Beltram F Beere HE Linfield EH Davies AG Ritchie DA 《Optics letters》2003,28(10):810-812
Chirped-superlattice quantum-cascade lasers are reported that emit at lambda approximately 85 microm (3.6 THz), which is to the authors' knowledge the longest wavelength demonstrated so far with this technology. Collected peak output powers of 1.5 mW per facet were measured at liquid-helium temperature, and a maximum operating temperature of 45 K was reached. Record low-threshold-current densities of 95 and 115 A cm(-2) were observed in pulsed and continuous-wave operation, respectively. For the latter, output powers of a few hundred microwatts are estimated at low temperatures. 相似文献
16.
We present an architecture permitting broad tuning of monolithic microchip lasers by using a wedged etalon. Full tuning from 282 to 314 nm is demonstrated by using a miniature Ce:LiCAF laser design, where tuning is achieved by translating the entire Ce laser cavity relative to the pump beam. The application of this technique to a range of microchip lasers will lead to extremely robust tunable monolithic lasers. 相似文献
17.
A.A. Betin D.A. Rockwell D.M. Filgas R.A. Reeder E.P. Ostby F.P. Strohkendl R.S. Baltimore 《Optics Communications》2008,281(11):3143-3148
We have demonstrated a loop phase-conjugate mirror that has produced up to 200 W phase-conjugate average output power at a 140% reflectivity for a CW input beam at a wavelength of 1.03 μm. A high conjugation fidelity was established by showing that more than 80% of the output beam power was contained within a 1.3-1.7 times diffraction limited beam after double passing a heavily aberrating amplifier chain. 相似文献
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19.
A Q-switched ytterbium-doped fiber laser(YDFL)is proposed and demonstrated using a newly developed multi-walled carbon nanotubes polyethylene oxide(MWCNTs-PEO)film as a passive saturable absorber(SA).The saturable absorber is prepared by mixing the MWCNTs homogeneous solution into a dilute PEO polymer solution before it is left to dry at room temperature to produce thin film.Then the film is sandwiched between two FC/PC fiber connectors and integrated into the laser cavity for Q-switching pulse generation.The laser generates a stable pulse operating at wavelength of 1060.2 nm with a threshold pump power of 53.43 mW.The YDFL generates a stable pulse train with repetition rates ranging from7.92 to 24.27 kHz by varying 980-nm pump power from 53.42 to 65.72 mW.At 59.55-mW pump power,the lowest pulse width and the highest pulse energy are obtained at 12.18μs and 143.5 nJ,respectively. 相似文献
20.
We present a high-precision optical phase-locking based on wideband acousto-optical frequency shifting.Increasing the modulating bandwidth stabilizes the loop at a high loop gain,thus improving phase correction capability.An optical phase-locked loop with a wide control bandwidth is constructed.The closed-loop residual phase error is only 0.26°or smaller than λ/1000.The loop exhibits excellent correction capability for high-frequency noises.The correctable frequency range reaches 35 kHz when the noise amplitude is ±λ/2,and becomes even wider for smaller noise amplitudes. 相似文献