Microstructure for suppressing parasitic oscillation of columnar laser gain medium

The invention discloses a microstructure for suppressing parasitic oscillation of a columnar laser gain medium. According to the microstructure, a sawtooth-shaped structure is formed in the side edgeof a laser gain medium in a machining or chemical corrosion mode, the sawtooth shape meets the condition that the ratio of the tooth height to the tooth pitch is (6: 1)-(10: 1) or a Brewster angle, and the sawtooth-shaped structure is round sawteeth or spiral sawteeth and is arranged in a single circle or multiple circles. Through the microstructure, parasitic oscillation of the laser gain mediumcan be suppressed, and meanwhile, the heat dissipation area and the pump light absorption efficiency of the gain medium crystal are effectively increased. The microstructure has the advantages of increasing the heat dissipation area of the crystal, eliminating the thermal lens effect and the like, and can be used for realizing high-energy, high-gain and high-beam-quality solid laser output.