Stable laser based on color centers in the OH:NaCl crystal tunable in the range 1.4 to 1.7 $\mu$m and operating at room temperature

Stable lasing has been obtained on $F_2^+$- and $F_2^+:O^{2-}$ color centers in additively colored OH:NaCl crystals. The laser operated at room temperature in the periodic-pulse ($f$ = 5 kHz, $\tau$ = 150 ns) and quasi-cw regimes. The laser wavelength was tunable in the range of 1.4 to 1.7 $\mu$m, with a peak output power of 50 mW at 1.54 $\mu$m. The NaCl laser was operated for 30 h without any observable degradation was over a 20-day period at 300 K. The output power of the laser remained constant over this time.