共查询到20条相似文献,搜索用时 31 毫秒
1.
Rui-Hua Wang Xiu-Wei Fan Hai-Xia Wang Hai-Tao Huang Li Zhu Jing-Liang He 《Laser Physics》2009,19(9):1882-1885
The generation of passively Q-switched mode-locking (QML) pulse has been obtained from a diode-pumped Nd:GdVO4 laser with a LT-InGaAs wafer as saturable absorber as well as output coupler. Under the incident pump power of 10 W, an average
output power of QML was 1.8 W with a Q-switched repetition rate of 280 kHz. The pulse duration of Q-switched pulse is about
160 ns and mode-locked pulse within the Q-switched envelope had a repetition rate of 410 MHz. It is indicated that the present
LT-InGaAs is a very promising device in the field of mode locking solid-state laser, and we are sure that it will be complete
pure cw mode locking with single beam output easily after further optimizing in the parameter such as saturation fluence,
modulation depth, recovery time and damage threshold in semiconductors. 相似文献
2.
An xenon-lamp-pumped passively Q-switched and mode-locked (QML) Nd:YAG laser with Co:LMA saturable absorber at 1.3 μm is realized
in a straight cavity. The modulation depth of mode locking pulse has reached 100%. The pulse energy and the pulse width of
QML laser have been measured. The pulse width of the mode-locking laser is estamated to be 940 ps. 相似文献
3.
S. P. Ng D. Y. Tang J. Kong L. J. Qin X. L. Meng Z. J. Xiong 《Applied physics. B, Lasers and optics》2005,81(4):511-515
We report on a diode-pumped passively mode-locked Nd:Gd0.64Y0.36VO4 laser with a Cr4+:YAG saturable absorber. Q-switched mode locking (QML) with 90% modulation depth was obtained. The peak power of the mode-locked pulse near the maximum of the Q-switched envelope was estimated to be about 1.7 MW at the pump power of 12 W. Besides QML, continuous-wave mode locking was also experimentally realized, for the first time to our knowledge, in the laser under a strong intracavity pulse energy fluence. The mode-locked pulse width is about 2.96 ps at a repetition rate of 161.3 MHz. 相似文献
4.
G. Zhang S. Z. Zhao Y. F. Li G. Q. Li D. C. Li K. J. Yang K. Cheng H. B. Ge Z. G. Yu 《Laser Physics》2009,19(11):2082-2085
Simultaneous mode locking had been obtained in acousto-optic Q-switched Nd:LuVO4 laser by using a Z-type cavity. Pulses with great average output power and narrow pulse width were observed in our experiment.
The modulation depth is nearly 90% and the width of Q-switched envelope is about 70 ns, and both maintained constant with
the increase of pump power. The maximum average output power of 1.83 W was obtained when the incident pump power was 6.78
W and the Q-switched envelop repetition frequency was 30 kHz. Also the average pulse width of the mode locking among the Q-switched
envelope is estimated to be about 200 ps. 相似文献
5.
By using a-cut Nd:Lu0.15Y0.85VO4 mixed crystal as laser gain medium, a diode-pumped passively Q-switched and mode-locked (QML) laser with a GaAs saturable
absorber in a Z-type folded cavity is demonstrated for the first time. The Q-switched mode-locked laser pulses with about 90% modulation
depth are obtained as long as the pump power reached the oscillation threshold. The repetition rate of the passively Q-switched
pulse envelope ranges from 50 to 186 kHz as the pump power increases from 0.915 to 6.520 W. Under an incident pump power of
6.52 W, the QML pulses with the largest average output power of 694 mW, the shortest pulse width of 200 ns and the highest
pulse energy of 3.73 μJ are obtained. The mode-locked pulse width inside the Q-switched envelope is estimated to be about
275 ps. The experimental results show that Nd:Lu0.15Y0.85VO4 is a promising mixed crystal for QML laser. 相似文献
6.
Yan Zhang Dechun Li Kejian Yang Guiqiu Li Gang Zhang Kang Cheng 《Optics Communications》2010,283(24):5121-5125
By using both acousto-optic (AO) modulator and GaAs saturable absorber, a diode-pumped doubly Q-switched and mode-locked (QML) YVO4/Nd:YVO4 laser is presented. The average output power and the pulse width of the Q-switched envelope have been measured. The Q-switch pulse energy of the doubly QML laser are higher than that only with GaAs. The stability of the QML laser with the dual-loss-modulation is significantly improved if compared to that only with GaAs.The experimental results show that the doubly QML YVO4/Nd:YVO4 laser has nearly 80% modulation depth and deeper than that of the singly passively QML pulse. The doubly Q-switched mode-locked pulse inside the Q-switched envelope has a repetition rate of 111 MHz and its pulse width is estimated to be about 700 ps. By using a hyperbolic secant square function and considering the Gaussian distribution of the intracavity photon density, the coupled equations for diode-pumped dual-loss-modulated QML laser is given and the numerical solutions of the equations are in good agreement with the experimental results. 相似文献
7.
G. Zhang S. Zhao Y. Li G. Li D. Li K. Yang T. Li K. Cheng H. Ge Y. Zhang Z. Yu 《Laser Physics》2010,20(6):1307-1311
A diode-pumped Q-switched and mode-locked (QML) Nd:LuVO4/KTP green laser with acousto-optic modulator (AOM) and Cr4+:YAG saturable absorber is presented. By inserting an AOM into the laser cavity, the stability of the QML green laser pulse with AO and Cr4+:YAG is improved, the modulation depth is increased and the pulse width of Q-switched pulse envelope is significantly compressed in comparison with that of the singly passively QML green laser with Cr4+:YAG. The experimental results show that the peak power of the doubly QML green laser pulse is much higher than that of the singly passively QML green laser pulse. 相似文献
8.
Tianli Feng Shengzhi Zhao Kejian Yang Guiqiu Li Dechun Li Jia Zhao Bin Zhao Yonggang Wang 《Optik》2014
By using mixed crystal Nd:Lu0.15Y0.85VO4 as laser medium, KTP as frequency-doubling crystal, a diode-pumped intracavity-frequency-doubled Q-switched and mode-locked (QML) Nd:Lu0.15Y0.85VO4/KTP green laser with acousto-optic (AO) modulator and central semiconductor saturable absorption mirror (C-SESAM) is realized by using a V-type cavity. The QML laser characteristics such as the pulse width, single-pulse energy, have been measured for different modulation frequencies of the AO modulator. In comparison with the singly passively QML green laser with central SESAM, the doubly QML green laser can generate more stable and shorter pulses with higher peak power. Based on the coupled rate equations for a diode-pumped doubly QML green laser with AO and C-SESAM, in which the saturated absorption mechanism of C-SESAM is considered, the recurrence relation of the relative amplitude of the mode-locking pulses is given and the related numerical simulations are in good agreement with the experimental results. 相似文献
9.
A diode-pumped dual-loss-modulated Q-switched and mode-locked (QML) Nd:Lu0.15Y0.85VO4 laser at 1.34 μm with single-walled carbon nanotube saturable absorber (SWCNT-SA) and acousto-optic (AO) modulator is demonstrated.
The modulation depth of the dual-loss-modulated QML laser reaches 90%, being deeper than 75% that obtained by the single passively
QML laser. The stability of the hybrid QML laser is significantly improved if compared to that only with SWCNT-SA. The Q-switched
pulse energy and the Q-switched pulse width of the QML laser with the dual-loss-modulation are 487 and 27% of those only with
SWCNT-SA, respectively. 相似文献
10.
By using both V3+:YAG and Co:LMA saturable absorbers, an xenon-lamp-pumped doubly passively Q-switched and mode-locked (QML) Nd:YAG laser at
1.3 μm in a straight cavity is realized for the first time. The modulation depth of QML pulse has nearly reached 100%. The
experimental results shows that the doubly passively Q-switched and mode-locked (QML) laser can generate shorter Q-switch
envelope pulse with higher average peak power in comparison to the singly passively QML laser with V3+:YAG or Co:LMA saturable absorber. 相似文献
11.
Fei Chen Xin Yu Xudong Li Renpeng Yan Cheng Wang Deying Chen Zhonghua Zhang Junhua Yu 《Optics Communications》2011,284(2):635-639
A high power diode-end-pumped passively Q-switched and mode-locking (QML) Nd:GdVO4 laser at 912 nm was demonstrated for the first time, to the best of our knowledge. A Z-type laser cavity with Cr4+:YAG crystals as the intracavity saturable absorber were employed in the experiments. Influence of the initial transmission (TU) of the saturable absorber on the QML laser performance was investigated. Using the TU = 95% Cr4+:YAG, as much as an average output power of 2.0 W pulsed 912 nm laser was produced at an absorbed pump power of 25.0 W, then the repetition rates of the Q-switched envelope and the mode-locking pulse were ~ 224 kHz and ~ 160 MHz, respectively. Whereas the maximum output power was reduced to 1.3 W using the TU = 90% Cr4+:YAG, we obtained a 100% modulation depth for the mode-locking pulses inside the Q-switched envelope. 相似文献
12.
A diode-pumped passively Q-switched and mode-locked Nd:GdVO4 laser at 1.34 μm with V3+:YAG as the saturable absorber is realized in a V-type folded cavity. About 100% modulation depth of mode locking can be obtained as long as the pump power reaches the oscillation threshold. The width of the mode-locked pulse is estimated to be less than 280 ps with 200 MHz repetition rate within an about 980 ns-long Q-switched pulse envelope. A maximum output power of 200 mW and Q-switched pulse energy of 5.7 μJ is obtained. 相似文献
13.
By using double-mixed crystal Nd:Lu0.15Y0.85VO4 as laser medium, a diode-pumped doubly Q-switched and mode-locked (QML) Nd:Lu0.15Y0.85VO4 laser with acousto-optic (AO) modulator and central semiconductor saturable absorption mirror (SESAM) is realized for the
first time. The Q-switched envelope modulation depth is nearly 100%.The average output power and the pulse width of the Q-switched
envelope etc. for different AO modulator repetition rates have been measured. The experimental result show that Nd:Lu0.15Y0.85VO4 crystal is an excellent laser medium for doubly QML lasers. 相似文献
14.
15.
Passive mode locking of a Nd:YAG laser with co-doped Nd, Cr:YAG as saturable absorber 总被引:1,自引:0,他引:1
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We demonstrate the characteristics of relatively low saturation intensity using co-doped Nd, Cr:YAG as saturable absorber for passively mode locking the Nd:YAG laser. The difference of the saturation intensity between Q-switched and mode-locked operation in co-doped Nd, Cr:YAG was only one to two orders of magnitude, while Cr:YAG was generally reported at a difference of five orders of magnitude. More than 80% mode locking modulation depth was achieved at an incident pump power of 4.4W, corresponding to an intracavity intensity of 6×10^4W/cm^2, using a 68cm long plano-concave cavity. 相似文献
16.
A diode-pumped passively Q-switched mode-locked (QML) intracavity frequency-doubled Nd:GdVO4/KTP green laser with a semiconductor saturable absorber is presented. Nearly 100% modulation depth for the mode-locked green pulses can be achieved at any pump power over 1.92 W. The width of the mode-locked green pulse was estimated to be about 150 ps. The mode-locked pulse interval within the Q-switched envelope of 320 ns and the repetition rate of 97.5 kHz were obtained, at an incident pump power of 4.4 W. The repetition rate of the mode-locked green pulses inside the Q-switched envelope was 140 MHz. 相似文献
17.
M. Li S. Zhao G. Q. Li K. Yang D. Li J. Wang J. An 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(1):181-186
A diode-pumped passively Q-switched mode-locked (QML)
intracavity frequency doubled c-cut Nd:GdVO4/KTP green laser with a
LT-GaAs saturable absorber is presented. More than 90% modulation depth
for the mode-locked green pulses has been achieved. Using the hyperbolic
secant function methods, a developed rate equation model for Q-switched and
mode-locked lasers considering the Gaussian spatial distribution of the
intracavity photon intensity, the influences of continuous pump rate, the
upper state lifetime of the active medium, and the excited-state lifetime of
the saturable absorber, was proposed. With this developed model, the
theoretical results are in good agreement with the experimental results and
the width of the mode-locked green pulse was estimated to be about 380 ps. 相似文献
18.
The efficient cw mode locking (cw-ML) regime was demonstrated in Nd:YVO4 laser by means of saturable absorber mirror (SAM). The 0.3-at.% Nd3+ doped 10-mm-long YVO4 crystal end pumped by 20-W diode module with a beam shaper was applied as a gain medium located in the close vicinity to
the rear flat mirror of the first arm of Z-type resonator of 316 cm total length with two curved mirrors of 100-cm curvature
radii. The SAM of 2%-saturable absorptance and saturation fluence of 50 μJ/cm2 was mounted at the opposite end of a resonator. The developed “dynamically stable” cavity design mitigates detrimental role
of thermal aberration in gain medium, enforcing clean perfect mode locking even for the highest pump densities. The cw-ML
pulses with 47.5 MHz repetition rate and pulse durations in the range of 15–20 ps were observed for a wide range of pump powers
and output coupler losses. In the best case, for 32% of output coupler transmission, up to 6.2 W of average power with near
35% slope efficiency was achieved. The thresholds for Q-switched ML, cw-ML regimes were 2.67 W and 6.13 W of pump power, respectively.
For the maximum pump power of 20 W we obtained 133 nJ of pulse energy with 16-ps pulse duration, resulting in a peak power
higher than 8 kW. The threshold energy density at SAM giving the QML regime was estimated to be about 30 μJ/cm2, threshold of cw-ML regime was 220 μJ/cm2. 相似文献
19.
The properties of low-frequency fluctuations in semiconductor lasers with optical feedback from a long external cavity are experimentally studied. Frequency-locking of the laser light output to the injection current modulation is observed when the modulation frequency approaches the external cavity mode. The modulation frequency for the successful frequency-locking is always less than the external cavity mode frequency and the locking domains as a function of the modulation amplitude is asymmetric with respect to the frequency detuning. 相似文献
20.
Reliable Q-switched and mode-locked operation of Yb-doped fiber lasers is investigated by employing an acousto-optic modulator
(AOM) in a linear cavity configuration. The widths and shapes of the Q-switched envelopes mainly depend on the external modulation
frequency of the AOM and near symmetric Q-switched pulses can be generated. Within the Q-switched envelopes, harmonic mode-locked
pulses with near 100% modulation depth at the 40 MHz repetition rate are experimentally observed. 相似文献