The influence of the inhomogeneous gain profile on the spatio-temporal dynamics of broad-area class B lasers

Abstract

A study on the spatio-temporal dynamics of broad-area Nd:YAG (yttrium aluminium garnet), Nd-doped phosphate glass and Nd-doped silicate glass lasers is presented to show the influence of the inhomogeneous gain profile and cross-relaxation phenomena on the spatio-temporal dynamics of the system. The suppression of the order-disorder transition shown in Cabrera et al (2006 Opt. Lett. 31 1067) for homogeneously broadened class B lasers is found for both glass lasers, independently of the strength of the cross-relaxation mechanisms. The results obtained indicate that a higher degree of inhomogeneous broadening leads to suppression of the filamentation in the transverse intensity pattern.

Self-acousto-optic modulation and orthogonality violation in the transverse modes of a broad-area Nd-doped yttrium-aluminum-garnet single-shot laser

“…The experimental setup is the same as used in Refs. [13] and [14]. We use an air-cooled, single-shot, low-pulse-energy (<50 mJ), flash-lamp-pumped prototype.…”

“…In fact, the thermal-induced asymmetry of the index of refraction has been identified as responsible for the NOMs in these systems. In a recent work [13], an intensity modulation induced by the interference of NOMs was found in various single-shot Nd doped solid-state lasers where thermal effects are negligible. In the present study we further analyze the onset of NOMs both experimentally and theoretically under these conditions, and we show that, for single-shot pulsed lasers, the asymmetric gain profile induced by the pump can be a sufficient effect to generate NOMs.…”

Stabilization of class-B broad-area laser emission by external optical injection

“…In the former case stabilization of the lasing profile was observed for some specific laser parameters in [15] by limiting the transverse extension of pumping to be about the scale of the unstable field components so that these unstable modes could not develop. The influence of the boundaries of the pumping region was found to be suppressed in the case of strongly inhomogeneous broadening of the gain profile of the active medium [16][17][18].…”