Active rejection-enhancement of spectrally adaptive liquid crystal geometric phase vortex coronagraphs

TL;DR

This paper explores how tunable liquid crystal defects can improve the spectral rejection efficiency of vector vortex coronagraphs, addressing manufacturing and spectral limitations.

Contribution

It introduces a method to enhance coronagraph rejection capabilities using self-engineered liquid crystal topological defects.

Findings

Enhanced rejection efficiency demonstrated

Design models evaluated for device optimization

Spectral adaptability achieved through liquid crystal tuning

Abstract

Geometric phase optical elements made of space-variant anisotropic media customarily find their optimal operating conditions when the half-wave retardance condition is fulfilled, which allows imparting polarization-dependent changes to an incident wavefront. In practice, intrinsic limitations of man-made manufacturing process or the finite spectrum of the light source lead to a deviation from the ideal behavior. This implies the implementation of strategies to compensate for the associated efficiency losses. Here we report on how the intrinsic tunable features of self-engineered liquid crystal topological defects can be used to enhance the rejection capabilities of spectrally adaptive vector vortex coronagraphs. We also discuss the extent of which current models enable to design efficient devices.