Microwave control of the interaction between two optical photons

TL;DR

This paper demonstrates how microwave fields can manipulate interactions between optical photons stored as Rydberg polaritons, enabling control over photon coherence and retrieval, with implications for quantum information processing.

Contribution

It introduces a method to control photon interactions via microwave-induced dipole-dipole interactions in Rydberg polaritons, showing selective retrieval of single photons.

Findings

Microwave fields induce strong dipole-dipole interactions.

Coherence of multi-excitation polariton modes is destroyed.

Single-photon modes are preferentially retrieved.

Abstract

A microwave field is used to control the interaction between pairs of optical photons stored in highly excited collective states (Rydberg polaritons). We show that strong dipole-dipole interactions induced by the microwave field destroy the coherence of polariton modes with more than one Rydberg excitation. Consequently single-polariton modes, which correspond to single stored photons, are preferentially retrieved from the sample. Measurements of the photon statistics of the retrieved light field also reveal non-trivial propagation dynamics of the interacting polaritons.