Diode-End-Pumped Linear-Polarized Single-Longitudinal-Mode Operation of a Tm:LuAG Laser at Room Temperature

We present a novel method to achieve linear-polarized single-longitudinal-mode (SLM) operation of a Tm:LuAG laser. Linear polarization of output laser can be guaranteed by placing one 0.1 mm F-P etalon at the Brewster angle in the cavity. The other 1 mm F-P etalon is turned to obtain an SLM laser. The maximum output power of the linear-polarized SLM laser is 84 mW. The central wavelength is 2,022 nm. The polarization degree is 30 dB. The output beam is at the fundamental mode. The power instability is less than 1%. The long-term frequency stability of the SLM laser is 3.56 · 10⁻⁷.