高重频大能量亚纳秒板条激光放大器研究

Research on high-repetition frequency and high energy sub-nanosecond slab laser amplifier

高重频大能量亚纳秒固体激光器具有重复频率高、单脉冲能量大、峰值功率高等特点,在国防军事工业加工等领域具有广泛的应用前景。本文报道了一种基于板条多程放大的亚纳秒激光放大器。种子光为重复频率1 kHz、平均功率4.5 W、脉冲宽度700 ps、波长1064 nm的基模激光,经过光束整形以匹配板条放大器口径,放大级采用角度复用及偏振变换实现四程放大,最终实现了重频1 kHz、单脉冲能量189 mJ、脉冲宽度720 ps、光束质量2倍衍射极限的亚纳秒激光输出。

High-repetition frequency and high energy sub-nanosecond solid-state lasers have the characteristics of high-repetition frequency,large single pulse energy and high peak power,which have a wide application prospect in the fields of national defense,military industry and industrial processing.In this paper,a sub-nanosecond laser amplifier based on slab multi-pass amplification is proposed.The seed light is a fundamental mode laser with a repetition frequency of 1 kHz,an average power of 4.5 W,a pulse width of 700 ps and a wavelength of 1064 nm.Then,the laser beam is shaped to match the caliber of the slab amplifier.The amplification stage adopts angle multiplexing and polarization transformation to achieve four-way amplification.Finally,a sub-nanosecond laser output with a frequency of 1 kHz,a single pulse energy of 189 mJ,a pulse width of 720 ps and a beam mass of 2 times the diffraction limit is achieved.