High-power Q-switched laser with high-order Laguerre-Gaussian modes: application for extra-cavity harmonic generations

Abstract

We present a compact efficient scheme for generation of high-order Laguerre-Gaussian TEM (p,0) modes in a diode-pumped actively Q-switched Nd:YVO(4) laser. The resonator is composed of two plane mirrors with an intracavity concave lens to expand the cavity mode size for generating a high-power Laguerre-Gaussian TEM(5,0) mode. We further confirm that the TEM(5,0) mode is noticeably superior to the TEM(0,0) mode in the processes of second and third harmonic generations.