Red, orange, and dual wavelength vortex emission from Pr:WPFGF fiber laser using a microscope slide output coupler.

Visible vortex beams have a large array of applications; however, the sources are often large or complex. Here, we present a compact vortex source with red, orange, and dual wavelength emission. This Pr:Waterproof Fluoro-Aluminate Glass fiber laser uses a standard microscope slide as an interferometric output coupler, yielding high quality first order vortex modes in a compact setup.

Unidirectional ring vortex laser using a wedge-plate shearing interferometer.

In response to growing demand from optical vortex (OV) beam applications, numerous generation techniques have been developed competing in power scalability, purity, and wavelength flexibility. Direct vortex emission from lasers typically grants access to efficient, high power, and pure mode generation. In this work we demonstrate a compact, unidirectional Nd:YVO ring laser with an intracavity wedge-plate shearing interferometer (WPSI) as an output coupler, which converted the internal Gaussian mode to LG (Laguerre-Gaussian OV) output.

>30 W vortex LG or HG laser using a mode transforming output coupler.

High-power vortex light generated directly from lasers will help drive their applications in material processing, optical manipulation, levitation, particle acceleration, and communications, but limited power has been achieved to date. In this work, we demonstrate record vortex average power of 31.3 W directly from a laser, to the best of our knowledge, using an interferometric mode transforming output coupler to convert a fundamental mode Nd:YVO laser into a LG vortex output.

Sampling a vortex from a Gaussian beam using a wedge-plate shearing interferometer.

Many vortex-generation techniques have been developed to address a range of potential applications, exploiting their unique amplitude and phase profiles and their possession of orbital angular momentum. In this work, we present what may be the simplest method of vortex beam generation, requiring only a wedged optic: the wedge-plate shearing interferometer (WPSI). We show that the WPSI can reflect a first order Laguerre-Gaussian vortex beam () with a theoretical purity of >99 from an input fundamental Gaussian beam, with 98% purity experimentally demonstrated.

Vortex laser by transforming Gaussian mode with an interferometric output coupler.

Generation of vortex beams directly from the laser source can be limited in power and efficiency, or to specific pump sources and gain media. Here, we propose a new high power and high efficiency vortex laser methodology with interferometric mode transformation as output coupling, which uses high power handling and low loss optics that have wavelength versatility. Experimental demonstration is made in a diode-pumped Nd:YVO laser using an imbalanced Sagnac interferometer as output coupler producing high quality vortex output beams (M = 2.