Ultracompact, dynamically controllable circularly polarized laser enabled by chiral metasurfaces

TL;DR

This paper presents a novel ultracompact chiral metasurface laser capable of dynamically switching between linear and circular polarization states, offering tunable, strong circularly polarized laser emission through simple design and control methods.

Contribution

The work introduces a low-cost, ultrathin chiral metasurface laser that enables dynamic control of circular polarization using quantum gain media and pump polarization, advancing CP laser technology.

Findings

Lasing emission can be transformed from linear to circular polarization.

Switching between right- and left-handed circular polarization is achieved.

The design allows dynamic control of lasing polarization via pump polarization.

Abstract

We demonstrate a simple, low-cost and ultracompact chiral resonant metasurface design, which, by strong local coupling to a quantum gain medium (quantum emitters), allows to implement an ultra-thin metasurface laser, capable of generating tunable circularly polarized coherent lasing output. According to our detailed numerical investigations the lasing emission can be transformed from linear to circular and switch from right- to left-handed circularly polarized (CP) not only by changing the metasurface chiral response but also by changing the polarization of a linearly polarized pump wave, providing thus dynamic lasing-polarization control. Given the increasing interest for CP laser emission, our chiral metasurface laser design proves to be a versatile yet straightforward strategy to generate strong and tailored CP emission laser, promising great potential for future applications in both photonics and materials science.