Photon Subtraction by Many-Body Decoherence

TL;DR

This paper explores how scattering in a Rydberg atomic ensemble causes spatial decoherence of stored photons, and demonstrates a quantum coherence-protection mechanism enabling robust single-photon subtraction.

Contribution

It provides an exact theoretical solution for many-body scattering-induced decoherence and experimentally demonstrates a novel coherence-protection process for quantum light manipulation.

Findings

Demonstrated a correlated coherence-protection effect in photon scattering

Provided an exact solution for many-body scattering-induced decoherence

Showed robust single-photon subtraction using the coherence-protection mechanism

Abstract

We experimentally and theoretically investigate the scattering of a photonic quantum field from another stored in a strongly interacting atomic Rydberg ensemble. Considering the many-body limit of this problem, we derive an exact solution to the scattering-induced spatial decoherence of multiple stored photons, allowing for a rigorous understanding of the underlying dissipative quantum dynamics. Combined with our experiments, this analysis reveals a correlated coherence-protection process in which the scattering from one excitation can shield all others from spatial decoherence. We discuss how this effect can be used to manipulate light at the quantum level, providing a robust mechanism for single-photon subtraction, and experimentally demonstrate this capability.