Spatially Localized Structures in a Self-Imaging Semiconductor Laser Cavity: Diffraction and Complex Non-linearity Management

In recent years, degenerate laser cavities have gathered attention for their versatility in the transverse structuration of laser emission [1], [2]. In non-linear optics, they are also used to generate patterns of temporally localized structures [3]. Degenerated laser system with high Fresnel number and saturable absorption are also suited for spatial localized structure (SLS). They appear as individually addressable peaks of lights in the transverse plane of the laser system [4]. In this work, we design a spatially degenerated self-imaging laser cavity integrating a slow saturable absorber semiconductor mirror (SESAM) and a high gain (
$\sim$
15%) semiconductor mirror for SLS generation. The optical cavity is composed of two high numerical aperture (0.2 NA) and low aberrations lenses in a 4-f configuration. It improves the degenerated system response while allowing for normal and anomalous diffraction tuning. A thin
$(< \lambda)$
chromium layer was deposited on the gain surface to define an area with strong absorptive boundary condition for light particle observation.