# Coherent population oscillations and an effective spin-exchange interaction in a $\mathcal{PT}$ symmetric polariton mixture

## TL;DR

This paper explores a two-species exciton-polariton system in a double well, demonstrating $ ext{PT}$ symmetry, long-term coherent oscillations, and simulating spin-1/2 particle interactions with potential applications in quantum simulation.

## Contribution

It identifies conditions for $ ext{PT}$ symmetry in a polariton mixture and shows how the system can mimic spin exchange interactions and sustain coherent population oscillations.

## Key findings

- System exhibits $ ext{PT}$ symmetry under specific conditions.
- Long-term coherent population oscillations observed.
- Simulates spin-1/2 particle dynamics with exchange interactions.

## Abstract

We study a two-species mixture of exciton-polaritons with self- and cross-interaction nonlinearities in a double well structure, in the presence of relaxation and continuous pumping. We identify the conditions that render the system parity-time ($\mathcal{PT}$) symmetric, and investigate its dynamic and static properties. We show that the system can exhibit long-term coherent oscillations of populations of the two polaritonic components between the two potential wells, and can simulate the dynamics of a pair of spin-1/2 particles (qubits) in the presence of exchange interaction.