Stable, Single Frequency Er:YAG Lasers at 1.6 μm

Stable, single frequency lasers in the eye-safe band are essential for coherent remote sensing. We describe an Er:YAG laser that is resonantly pumped using diode lasers, and produces a polarized, single frequency, diffraction limited beam at 1645 nm with a frequency stability suitable for single-shot velocity measurements with a precision< 0.1 ms⁻¹.