Low-intensity-noise single-frequency CW 1080 nm laser by employing a laser crystal with the small stimulated-emission cross section

Abstract

An effective approach to obtain a single-frequency laser with low intensity noise is presented in this paper, which is implemented by employing a gain medium with the small stimulated-emission cross section (SECS). When the adopted Nd:YAP (Nd:YAlO3) gain medium with SECS of 4.6×10−19 cm2 is replaced by Nd:CYA (Nd:CaYAlO4) gain medium with SECS of 1.04×10−19 cm2, the frequency of measured intensity noise reached shot noise limit obviously reduces from 2.49 to 1.5 MHz, which agrees well with the theoretical predictions. On this basis, a single-frequency continuous-wave (CW) Nd:CYA laser with low intensity noise is first achieved. The attained output power of the Nd:CYA laser is 1.12 W. The achieved single-frequency CW 1080 nm laser will satisfy the requirements of the squeezed and entangled light generation.