Insertable monolithic ring cavity laser for high output power single-frequency operation

A novel insertable monolithic ring laser based on a Nd:YAG-YAG bonded crystal was proposed for high output power single-frequency operation. In a proof-of-principle experiment, the unidirectional resonator pumped by an 808 nm diode laser was constructed with a half-wave plate and a TGG etalon, thus achieving both structural stability and functional tunability. A single-frequency laser with the output power of 4.1 W is obtained at 1064 nm, corresponding to the slope efficiency of 17.7 % and an optical-to-optical efficiency of 11.8 %. The power fluctuation is measured to be within ±1% over 20 min. The average beam quality factor M2 is measured to be 2.07.