Polarization properties of laser-diode-pumped micro-grained Nd:YAG ceramic lasers

TL;DR

This paper investigates the polarization behaviors of micro-grained Nd:YAG ceramic lasers pumped by laser diodes, revealing stable linear polarization in some configurations and complex elliptical polarization with dynamic instabilities in others.

Contribution

It provides a detailed analysis of polarization properties in different cavity configurations of LD-pumped Nd:YAG ceramic lasers, highlighting the conditions for stable and unstable polarization states.

Findings

Stable linearly-polarized single-frequency oscillations observed in external cavity scheme.

Elliptically-polarized operations with dynamic instabilities in thin-slice laser scheme.

Self-induced antiphase modulations among circularly-polarized components at higher pump powers.

Abstract

Detailed polarization properties have been examined in laser-diode-pumped (LD-pumped) micro-grained ceramic Nd:YAG lasers in different microchip cavity configurations. Stable linearly-polarized single-frequency oscillations, whose polarization direction coincide with that of an LD pump light, were observed in an external cavity scheme. While, in the case of a thin-slice laser scheme with coated reflective ends, elliptically-polarized single-frequency operations took place in the low pump-power regime and dynamic instabilities appeared, featuring self-induced antiphase modulations among counter-rotating circularly-polarized components having slightly different lasing frequencies, with increasing the pump power.