Author Affiliations
Abstract
1 State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
3 University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100049, China
A Ti:sapphire crystal with a diameter of 235 mm and thickness of 72 mm was grown by the heat exchange method (HEM). The absorption intensity of the crystal at 532 nm averaged at 91%. The figures of merit (FOMs) at different positions of the crystal were measured and the FOM value in the central region was found to reach 90. The transmittance laser beam was intact with no obvious distortions and had only a small deformation compared with the incident laser beam. A small-signal amplification experiment was performed on the Ti:sapphire crystal and a gain of more than 6 times was achieved with a pump energy density of 1.98 J/cm2. These tests indicate that the 235 mm Ti:sapphire crystal has excellent optical qualities and will further improve the energy output of a 10 PW laser system.
140.3280 Laser amplifiers 140.3590 Lasers, titanium 140.5560 Pumping Chinese Optics Letters
2018, 16(7): 071401
Author Affiliations
Abstract
1 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 ShanghaiTech University, Shanghai 200120, China
3 University of Chinese Academy of Sciences, Beijing 100039, China
We research some properties of parasitic lasing (PL) in the Ti:sapphire chirped pulse amplifier with the crystal diameter of 100 mm. The evolutionary process from the spontaneous emission to the PL and its influence on amplified output energy, spectrum, and beam profile are experimentally measured. The threshold of PL in the crystal is 22 J, and the output signal can still keep rising with the pump when the pump energy is below 38 J. The PL has no obvious impact on the output spectrum and beam profile besides the energy.
140.3280 Laser amplifiers 140.3590 Lasers, titanium 140.5560 Pumping Chinese Optics Letters
2017, 15(6): 061401
Author Affiliations
Abstract
1 State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100049, China
3 Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
We experimentally compare the output abilities of lightly and heavily doped Ti:Sapphire (Ti:S) amplifiers with diameters as large as 150 mm. Although a lightly doped Ti:S is more favorable to overcome parasitic lasing (PL) and transverse amplified spontaneous emission (TASE), the self-phase-modulation (SPM) effect becomes more pronounced when a longer crystal is used. Recompression of the amplified, stretched pulses can be seriously affected by the SPM effect. We then propose a temporal multi-pulse pump scheme to suppress PL and TASE in a thin, heavily doped Ti:S crystal. This novel temporal multi-pulse pump technique can find potential applications in 10 PW chirped-pulse amplification laser systems.
140.3280 Laser amplifiers 140.3590 Lasers, titanium 140.5560 Pumping Chinese Optics Letters
2017, 15(9): 091401
Author Affiliations
Abstract
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Shanxi 030006, China
A continuous-wave all-solid-state tunable Ti:sapphire laser with compact configuration is presented. The frequency-tuning range extends from 760 to 825 nm by rotating the birefringent filters. When the intracavity etalon is locked on the oscillating frequency of the laser and the length of the resonator is scanned by the piezoelectric ceramics transducer, a maximal continuous frequency-tuning range of 15.3 GHz is realized. The obtained Ti:sapphire laser is successfully applied to scan the saturation absorption spectroscopy of D1 transitions of Rb87 atoms around the wavelength of 794.97 nm.
140.3590 Lasers, titanium 140.3600 Lasers, tunable 140.3570 Lasers, single-mode 140.3560 Lasers, ring Chinese Optics Letters
2015, 13(7): 071401
Author Affiliations
Abstract
1 State Key Laboratory of Solidiˉcation Processing, Northwestern Polytechnical University, Xi'an 710072, China
2 School of Materials Science and Engineering, Chang'an University, Xi'an 710064, China
Morphology evolution of prior \beta grains of laser solid forming (LSF) Ti-xAl-yV (x \leq 11,y \leq 20) alloys from blended elemental powders is investigated. The formation mechanism of grain morphology is revealed by incorporating columnar to equiaxed transition (CET) mechanism during solidification. The morphology of prior \beta grains of LSF Ti-6Al-yV changes from columnar to equiaxed grains with increasing element V content from 4 to 20 wt.-%. This agrees well with CET theoretical prediction. Likewise, the grain morphology of LSF Ti-xAl-2V from blended elemental powders changes from large columnar to small equiaxed with increasing Al content from 2 to 11 wt.-%. The macro-morphologies of LSF Ti-8Al-2V and Ti-11Al-2V from blended elemental powders do not agree with CET predictions. This is caused by the increased disturbance effects of mixing enthalpy with increasing Al content, generated in the alloying process of Ti, Al, and V in the molten pool.
激光立体成形 混合元素粉末 Ti-Al-V合金 晶粒形貌 140.3590 Lasers, titanium 140.3390 Laser materials processing 160.2120 Elements Chinese Optics Letters
2011, 9(5): 051403
Author Affiliations
Abstract
Research Center of Space Laser Information Technology, Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
A compact all-solid-state continuous-wave (CW) laser at 1047 nm is developed based on Nd:LuLF, which is grown through the Czochralski technique. From the laser system, 1.3-W laser can be obtained, which corresponds to the slope efficiencies of 20.1% and 49.5% with respect to the incident and absorbed pump powers, respectively. To the best of our knowledge, this is the highest power level achieved at 1047 nm based on the Nd:LuLF crystal.
1047 nm Nd:LuLF 140.3390 Laser materials processing 140.3590 Lasers, titanium 160.3900 Metals Chinese Optics Letters
2011, 9(2): 021404
Author Affiliations
Abstract
State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072, China
The effect of solution temperature and cooling rate on microstructure and mechanical properties of laser solid forming (LSF) Ti-6Al-4V alloy is investigated. The samples are solutions treated at 900, 950, and 1000 C, followed by water quenching, air cooling, and furnace cooling, respectively. It is found that the cooling rate of solution treatment has a more important effect on the microstructure in comparison with the solution temperature. The martensite \alpha’ formed during water quenching results in the higher hardness and tensile strength but lower ductility of samples. With decreasing the cooling rate and increasing the solution temperature, the width of primary \alpha laths increases, and the aspect ratio and volume fraction decrease, which make the hardness and tensile strength decrease and the ductility increase.
激光立体成形 TC4钛合金 热处理 组织 性能 140.3390 Laser materials processing 140.3590 Lasers, titanium 160.3900 Metals Chinese Optics Letters
2009, 7(6): 06498
Author Affiliations
Abstract
Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 2018002 Graduate University of Chinese Academy of Science, Beijing 100049
A compact, all-solid-state, narrow-linewidth, pulsed 455-nm blue laser based on Ti:sapphire crystal is developed. Pumped by a 10-Hz, frequency-doubled all-solid-state Nd:YAG laser and injection-seeded by an external cavity laser diode, the narrow-linewidth 910-nm laser with pulse width of 20 ns is obtained from a Ti:sapphire laser. 3.43-mJ blue laser can be obtained from the laser system by frequency-doubling with BBO crystal. This research is very useful to determine the roadmap of developing the practical, high power blue laser. This kind of laser will have potential application for underwater communication.
全固态激光器 蓝光 单模 倍频 140.0140 Lasers and laser optics 140.3410 Laser resonators 140.3570 Lasers, single-mode 140.3590 Lasers, titanium Chinese Optics Letters
2009, 7(1): 0143
Author Affiliations
Abstract
1 State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800
2 Graduate School of the Chinese Academy of Sciences, Beijing 100039
We suggest and demonstrate an approach to generate a femtosecond multi-terawatt pulse train at repetition rate of 100 MHz in a 10-Hz chirped pulse amplification Ti:sapphire laser system. With an electro-optic Q-switch regenerative amplifier, we can obtain an adjustable repetition-rate chirped pulse train. After amplification and compression, the 100-MHz pulse train with 46-fs pulse width and 1-TW peak power per pulse is obtained in our 10-TW-class Ti:sapphire laser system.
140.3280 Laser amplifiers 140.3590 Lasers, titanium 320.5540 Pulse shaping 320.7090 Ultrafast lasers Chinese Optics Letters
2007, 5(s1): 166
Author Affiliations
Abstract
State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800
Micro-lens arrays were adopted to homogenize the beam profile of 532-nm pumping laser for the main amplifier of an intense femtosecond, chirped pulse amplification (CPA) Ti:sapphire laser. Experimental measurements showed a great improvement of the near-field pattern of the CPA beam after the main amplifier and the size of the focal spot was improved from 2.7 times diffraction limitation (DL) to 1.6 DL. The spot size focused by an f/4 off-axis parabola (OAP) in the target chamber was measured to be 5.8 micron (full-width at half-maximum (FWHM)), and a peak intensity of 2.6*10^(20) W/cm2 was obtained at the output power of 120 TW. Peak intensity exceeding 10^(21) W/cm2 or even 10^(22) W/cm2 can be expected with smaller f-number focusing configuration and wavefront correction.
钛宝石激光器 超快激光 光束整形 微光学 140.3590 Lasers, titanium 140.7090 Ultrafast lasers 140.3300 Laser beam shaping 350.3950 Micro-optics Chinese Optics Letters
2006, 4(10): 583
