The characteristics of supercontinuum produced by high-intensity femtosecond pulses were investigated under different interaction lengths, various pump intensities, different pump wavelengths at the fundamental 800 nm...The characteristics of supercontinuum produced by high-intensity femtosecond pulses were investigated under different interaction lengths, various pump intensities, different pump wavelengths at the fundamental 800 nm and its second-harmonic 400 nm. High transfer-efficiency supercontinuum with flat-top in liquid media was produced. As the main nonlinear mechanisms, the effects of self-phase modulation (SPM) and four-photon parametric emission were also investigated.展开更多
An efficient chirped-pulse amplification, Ti:sapphire laser system, has been developed using mainly domestic components. The gain-narrowing effect has been significantly overcome by shaping spectrum of seeding pulses....An efficient chirped-pulse amplification, Ti:sapphire laser system, has been developed using mainly domestic components. The gain-narrowing effect has been significantly overcome by shaping spectrum of seeding pulses. With a novel aberration-free stretcher and two stage multi-pass amplifiers, pulses with duration of 25 fs and 36-mJ energy have been obtained at 10 Hz repetition rate, using only less than 290 mJ green Nd: YAG pump energy. This corresponds to a 1.4 TW peak power and 32% main amplification efficiency. The energy stability of the laser systems is better than ± 3% .展开更多
基金Project supported by Hong Kong Research Grant Council Project HKUST 633.94P,the China National Climbing Plan,and the Laboratory of Optoelectronics and Informational Engineering,the State Education Commission.
文摘The characteristics of supercontinuum produced by high-intensity femtosecond pulses were investigated under different interaction lengths, various pump intensities, different pump wavelengths at the fundamental 800 nm and its second-harmonic 400 nm. High transfer-efficiency supercontinuum with flat-top in liquid media was produced. As the main nonlinear mechanisms, the effects of self-phase modulation (SPM) and four-photon parametric emission were also investigated.
文摘An efficient chirped-pulse amplification, Ti:sapphire laser system, has been developed using mainly domestic components. The gain-narrowing effect has been significantly overcome by shaping spectrum of seeding pulses. With a novel aberration-free stretcher and two stage multi-pass amplifiers, pulses with duration of 25 fs and 36-mJ energy have been obtained at 10 Hz repetition rate, using only less than 290 mJ green Nd: YAG pump energy. This corresponds to a 1.4 TW peak power and 32% main amplification efficiency. The energy stability of the laser systems is better than ± 3% .