Purity of Vector Vortex Beams through a Birefringent Amplifier

Vector vortex beams, a form of structured light, have been applied in many fields, from imaging to materials processing, $e.g.$ for tighter focusing and smaller spots than allowed by diffraction-limited beams. The latter application requires high-power vector beams of good purity (vector quality), a little-explored topic. This work presents a toolbox for studying the amplification of vector beams, outlining how to create these beams with high power and high purity, including the exciting discovery that the vector nature can be not just preserved, but even enhanced, by a judicious choice of medium. This study is a crucial step toward seeing vector vortex beams deployed in industry.