Unidirectional Ring TI3+:AL2O3 Laser Operation at the Wavelength of an Atomic Absorption Line Using Bi-Directional Passive Self-Injection

Passive self-injection locking (PSIL) laser spectral control yields efficiency close to that in the optimized non-selective cavity and avoids the optical damage of the selectors [1,2]. Its principle lies in the spectrally selective re-injection in the cavity of a part of the output beam. We show (theory, experiment) that such control entails as addition the principle of novel technique for producing in a purely optical and simple manner high power unidirectional ring laser generation which is spectrally fixed at a chosen reference atomic absorption line. Such lasers are of interest as wavelength standards, in laser isotope separation and in DIAL lidars.