Construction and characterization of a CO2 axicon-based Bessel-Gauss resonator

ABSTRACT We report the generation of Bessel-Gauss beams using a CO 2 laser resonator. The cavity is composed by a planeoutput mirror and a total re s ective axicon, this con Þ guration had been studied previously by Gutierrez-Vega etal [J.Opt.Soc.Am.A 20 , 2113-22 (2003)]. Bessel-Gauss beams are produced directly from the cavity. The useof a re s ective axicon instead of a refractive one results in reduction of surface-induced aberrations, minimizingabsorption and increasing the non-di  racting distance. This results in a higher power non-di  racting laser beamwith potential scienti Þ c and industrial applications. In order to characterize the resonator, we have obtainedits output transverse intensity distribution. Additionally, we have numerically and experimentally studied thee ects of mirror tilt on the output transverse mode structure. We have made numerical simulations of themisaligned resonator modes based on Bowers’s method [Appl. Opt. 31 , 1185-98 (1992)]. Direct comparison ofnumerical and experimental results allow us to estimate the di  ractive losses of the modes on the misalignedcavity and their dependence on the aligned bare cavity eigenmodes, thus providing valuable information of theoutput power dependence on mirror misalignment. Relevant experimental parameters and numerical procedureare fully described.