Generation of single frequency highly coherent high-order Laguerre Gaussian modes with Vertical-External-Cavity-Surface-Emitting-Laser

摘要

Laser beams operating at high-order Laguerre-Gauss (LG) modes have lots of applications in many areas including laser drilling and writing, optical manipulation, trapping and guiding of atoms [1,2]. In fact, the LG modes are the natural modes for a linear cavity using spherical mirrors and having axial symmetry of revolution[3]. We demonstrated that the Vertical External Cavity Surface Emitting Laser (VECSEL) is a very promoting laser technology for the generation of this kind of light beams [4]. Indeed, the VeCSEL design relies on small thickness quantum-well (QW) gain medium which minimizes non-linear optical interactions, thermal effects and possible astigmatism inside the semiconductor structure. The interplay of this 2 (2D) dimensions transverse gain medium with a low-loss cavity design permits the generation of single frequency high quality diffraction limited beam profiles.