1 kHz single frequency injection seeded Er:YAG laser with an optical feedback

A novel 1 kHz single-frequency, Q-switched Er-doped yttrium aluminum garnet (Er:YAG) laser pumped by a 1470 nm laser diode is demonstrated. The 500 ns, 5.52 mJ single-frequency, diffraction-limited pulses are obtained by using a ‘ramp-fire’ injection-seeding technique and an optical feedback archite