Optimizing the beam quality of high-energy pulse mid-IR Fe:ZnSe laser.

The mid-IR Fe:ZnSe laser has gained widespread attention due to its enormous potential with high-energy output. However, applications of Fe:ZnSe laser are limited by the beam quality. To optimize the beam quality of high-energy pulse Fe:ZnSe laser, this study presents a method of using spatial filtering in the resonator. Based on the theory of the ABCD transfer matrix and simulation of resonator stability and beam radius properties, the structure of the resonator was designed. Additionally, we study the output properties of Fe:ZnSe laser with different aperture diameters. We demonstrate when the aperture diameter D = 0.5 mm, the Fe:ZnSe laser output energy is 45.7 mJ and the beam quality is M x 2 = 2.11 , M y 2 = 2.29 , which is the best beam quality of using a pulse-pumped source to our knowledge. This method will guide for optimizing the beam quality of high-energy pulse mid-IR laser. [ABSTRACT FROM AUTHOR]