HIGH-ENERGY, DIODE-PUMPED, NARROW LINEWIDTH Cr:LiSAF LASER WITH A RING RESONATOR

摘要

The performance of a high-energy, diode-pumped, tunable, narrow-linewidth Q-switched Cr:LiSAF laser with a ring resonator utilizing two Total Internal Reflections (TIR) has been investigated, and a comparison of the performance of this resonator with the corresponding standing-wave resonator has been accomplished. The output characteristics and wavelength tuning curves in both cases have been measured. Under comparable experimental conditions, a Q-switched TEM_(00) transverse mode output of 22.3 mJ/pulse and 14 mJ/pulse has been obtained for the standing-wave and ring cavities, respectively, at 816 nm with a linewidth of 300 MHz. Unidirectional Q-switched operation of the ring resonator has been achieved, but the linewidth of the unidirectional ring laser was not single longitudinal mode. Such behavior of the Cr:LiSAF laser ring resonator can be explained by a slight inhomogeneous broadening of the Cr:LiSAF emission line. A laser linewidth of less than 300 MHz has been achieved by means of injection seeding with a cw distributed feedback (DFB) diode laser.