Electrically controlling vortices in a neutral exciton polariton condensate at room temperature

TL;DR

This paper demonstrates a novel method to electrically control vortex topological charges in exciton polariton condensates at room temperature using liquid crystal microcavities, enabling potential applications in photonic information processing.

Contribution

It introduces an electric tuning technique for polariton vortices via liquid crystal modulation, a significant advancement in controlling neutral bosonic condensates.

Findings

Vortices with topological charges +1, +2, -2, -1 are spontaneously formed.

Vortex charge is controllable by applying 1-10 V voltage.

The control relies on interplay of potential gradient, anisotropic microplates, and liquid crystal director.

Abstract

Manipulating bosonic condensates with electric fields is very challenging as the electric fields do not directly interact with the neutral particles of the condensate. Here we demonstrate a simple electric method to tune the vorticity of exciton polariton condensates in a strong coupling liquid crystal (LC) microcavity with CsPbBr$_3$ microplates as active material at room temperature. In such a microcavity, the LC molecular director can be electrically modulated giving control over the polariton condensation in different modes. For isotropic non-resonant optical pumping we demonstrate the spontaneous formation of vortices with topological charges of +1, +2, -2, and -1. The topological vortex charge is controlled by a voltage in the range of 1 to 10 V applied to the microcavity sample. This control is achieved by the interplay of a built-in potential gradient, the anisotropy of the optically active perovskite microplates, and the electrically controllable LC molecular director in our system with intentionally broken rotational symmetry. Besides the fundamental interest in the achieved electric polariton vortex control at room temperature, our work paves the way to micron-sized emitters with electric control over the emitted light's phase profile and quantized orbital angular momentum for information processing and integration into photonic circuits.