Chirped pulse amplification of femtosecond pulse sequences in a Ti: sapphire laser

Abstract

An amplified femtosecond pulse sequence is generated in a multi-TW Ti: sapphire chirped pulse amplification system (JG-II facility). The pulse interval of the pulse sequence is 14.8 ns, corresponding to a frequency of 67.5 MHz. The compressed pulse sequence can reach 122 mJ in 19 independent pulses with a pulse width of about 60 fs. The energy of the pulses declines from 20 mJ to 0.5 mJ, corresponding to a peak power from 1011 W to 1010 W. The pulse sequence has important applications in lengthening the lifetime of the laser produced plasma channel in air and in microfabrication.