Narrow-linewidth frequency doubling vortex light laser

Abstract

The invention discloses a narrow-linewidth frequency doubling vortex light laser, which comprises a pumping source, a pumping conversion device, a coupling lens group, a laser crystal, a temperature control device, a Brewster plate, a full-wave plate, a nonlinear optical crystal, a diaphragm and an output mirror which are sequentially arranged in the light propagation direction, wherein the pumping source outputs non-uniform pumping light after being coupled by the pumping conversion device and the coupling lens group; the left end face of the laser crystal and the output mirror form an optical resonant cavity, the Brewster plate is inserted into the cavity to polarize fundamental frequency vortex light, polarization selectivity loss is introduced by combining the full-wave plate and the nonlinear optical crystal to force the laser to operate in a single longitudinal mode, and the nonlinear optical crystal is used for frequency doubling of the vortex light in the cavity; and the outputmirror is slightly inclined. The narrow linewidth frequency doubling vortex light laser provided by the invention has the advantages of narrow linewidth, high mode purity, good light beam quality, simple structure, small size, convenience for system integration and the like.

Description

technical field [0001] The invention relates to the technical field of lasers, in particular to a narrow-linewidth frequency-doubled vortex optical laser. Background technique [0002] The Laguerre-Gaussian (LG) beam is a typical vortex beam, and the amplitude expression of the LG beam contains a phase factor term exp(imθ) (m is the topological charge), indicating that the beam is along the The direction of propagation forms a spiral phase wavefront, so it has orbital angular momentum; since the center of the LG beam is a phase singularity, the light intensity at the center is zero, so that its light intensity has a "doughnut" shape under normal circumstances. circular distribution. These properties are widely used in Optical Trapping and Manipulation, Super-resolution Microscopy, High-capacity Optical Communication, Quantum Information, etc., but these The application prospects have put forward higher requirements for the mode purity, monochromaticity, coherence and stabi...

AI Technical Summary

Problems solved by technology

Intracavity frequency doubling can greatly improve nonlinear conversion efficiency. Traditionally, the design of narrow linewidth laser output for intracavity frequency doubling is based on Gaussian beam pumping. By suppressing the generation of high-order transverse modes, the fundamental transverse mode ( TEM00) forms a stable oscillation in the cavity, and the output light is a single transverse mode laser. Although this method is simple, it cannot directly realize the laser output of vortex light with narrow linewidth in the cavity.

Chinese patent CN201910696589 discloses a single-frequency vortex laser, but due to the limitation of the optical fiber itself, it is impossible to achieve frequency doubling of vortex light in the cavity

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