A stable continuous wave mode-locked picosecond Ti：sapphire laser by using a fast semiconductor saturable absorber mirror （SESAM） is demonstrated. The laser delivers pulse width of 20 ps at a central wavelength of 813 nm and a repetition rate of 100 MHz. The maximum output power is 1.34 W with pump power of 7 W which corresponds to an optical^optical conversion efficiency of 19.1%.
This paper demonstrates the passively mode-locked Nd：GdVO4 laser operating on the ^4F3/2-^4I9/2 transition at 912 nm by using a semiconductor saturable-absorber mirror for passive mode locking, stable continuous wave modelocked 912nm laser was achieved with a repetition rate of 176 MHz. At the incident pump power of 17.7W, 22.6mW average output power of stable mode-locked laser was obtained with a slope efficiency of 0.3%.
We developed an adaptive optics system to correct the wave-front distortion of an intense fs laser beam from our multi-TW laser system, Jiguang II. In this paper, the instruments of the adaptive optical system are described and the experimental results of the closed-loop wave-front correction are presented. A distorted laser wave-front of 20 wavelengths of P-V values was corrected to 0.15 wavelength of P-V values. The beam quality of the laser system varies from 3.5 diffraction limit to 1.5 diffraction limit.
WANG Zhaohua JIN Zhan ZHENG Jiaan WANG Peng WEI Zhiyi ZHANG Jie
The intrinsic synchronization, multi-color outputs and related carrier-envelope phases (CEP) among pulses bring advantages to synchronously pumped femtosecond optical parametric oscillators and the pumping sources for broadband frequency comb generation and ultrashort waveform coherent syn-thesis. In this paper, we discuss our latest research results in this field, which cover the following as-pects: the phase relationship and energy conservation law in an OPO and related experimental verifi-cation; control of the pumping Ti:sapphire femtosecond laser's CEP by self-referencing technology, and its repetition-rate locking by piezoelectric transducer (PZT); CEP locking of the pulses from the OPO by beating the non-phase-matched visible outputs against pump supercontinuum to obtain a driving signal for a fast PZT on the OPO end mirror; the generation of a broadband frequency comb spanning from 400 nm to 2.4 μm with 1.2 kHz bandwidth; and the realization of coherent interference between phase controlled pump pulses and signal second harmonic pulses.
