Theoretical study on the characteristics of intracavity frequency doubling of a diode-pumped cesium vapor laser

摘要

Characteristics of intracavity frequency doubling of a diode-pump cesium vapor laser (Cs-DPAL) are studied in detail utilizing the rate equations theory. For intracavity frequency doubling of Cs-DPAL, very long nonlinear crystals such as LiB3O5 (LBO) and BiB3O6 (BIBO) with a relatively small effective nonlinear coefficient are required to get the maximum second harmonic (SH) power, and periodically poled crystals such as periodically poled KTiOPO4 (ppKTP) are promising. The reason for this phenomenon is that the simulated emission section is much higher, although it is favorable to reduce the laser threshold. For intracavity frequency doubling of Cs-DPAL in the quasi-two-level limit, the optimal length of nonlinear crystal is slightly shorter than the Cs-DPAL with the assumption of a very rapid transition from the 6(2)P(3/2) to 6(2)P(1/2) levels, and a qualitative interpretation is given. The SH power by intracavity frequency doubling of Cs-DPAL is also limited by the relatively slower collisional transfer rate from the 6(2)P(3/2) to 6(2)P(1/2) levels for higher pump power intensity. (C) 2016 Optical Society of America