Stable Subnanosecond Passively Q -Switched Laser End-Pumped by Intense Pulse with Compact Design

We demonstrate a stable compact passively Q -switched laser generating 40 μJ, subnanosecond ( < 1 ns) duration, 1064 nm pulses at a repetition rate of 10 kHz. With a composite Nd:YAG/Cr 4+ :YAG crystal in a simple and compact resonator end-pumped by intense 808 nm pulse, we effectively improve the stability of output laser pulses corresponding to the interpulse amplitude instability less 1% (rms) and the period jitter less 1 μs. These measured pulse-time characteristics agree with numerical simulations and the beam is close to the diffraction limit, with M 2 < 1 . 2. The excellent optical properties and structure make this laser to be an attractive source for high-resolution 3D imaging radars or other widespread applications.