Ground-state orbital angular momentum lasing from liquid crystal torons embedded in a microcavity

TL;DR

This paper shows how liquid crystal defects in a microcavity can generate laser beams with orbital angular momentum, useful for applications like optical tweezers.

Contribution

The paper introduces a novel method using liquid crystal torons to create lasing with nonzero orbital angular momentum.

Findings

Torons in a microcavity generate a non-Abelian gauge field that inverts ground and excited states.

The ground state produces robust lasing with nonzero orbital angular momentum in circular polarization components.

Abstract

Orbital angular momentum laser beams have many important practical applications, such as optical tweezers or ultrafast communications. Creating such beams represents an important challenge in photonics. Here, we demonstrate that torons, which are topological defects in liquid crystal textures, when embedded in a microcavity, generate a real-space non-Abelian gauge field responsible for the topological inversion of ground and excited states. The resulting ground state produces robust lasing with nonzero orbital angular momentum in each of the circular polarization components.

Torons, topological defects in liquid crystals, in a microcavity produce robust lasing with nonzero orbital angular momentum.

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