1.9 µJ external-cavity dumped ultra-broad-area semiconductor nanosecond laser

An external-cavity dumped nanosecond (ns) ultra-broad-area laser diode (UBALD) at around 966 nm with high pulse energy is demonstrated. A 1 mm UBALD is used to produce high output power and high pulse energy. A Pockels cell (PC) combines with two polarization beam splitters (PBSs) and is employed to cavity-dump a UBALD operating at 10 kHz repetition rate. At a pump current of 23 A, 11.4 ns pulses with a maximum pulse energy of ≈1.9 µJ and a maximum peak power of ≈166 W are achieved. The beam quality factor is measured to be M _x ²=19.5 in the slow axis direction and M _y ²=2.17 in the fast axis direction. Moreover, maximum average output power stability is confirmed, with a power fluctuation of less than 0.8% rms over 60 min. To the best of our knowledge, this is the first high-energy external-cavity dumped demonstration from an UBALD.