Stable, high-average-power, narrow-linewidth source at 2.1 μm pumped at 1.064 μm

We report stable, narrow-bandwidth operation of nanosecond degenerate OPO at 2.1 μm, for the first time, generating >2 W of average power in good beam-quality (M 2 <3.7) and passive power-stability of 0.6% rms over 1 hour.