Gravitational decoherence of photons

TL;DR

This paper extends a gravitational decoherence model to photons, deriving a master equation that predicts how gravitational fluctuations could cause decoherence in quantum optical experiments, enabling potential constraints on gravitational noise.

Contribution

It generalizes an existing gravitational decoherence model to include photons and derives a master equation for electromagnetic fields.

Findings

Interference experiments with long baselines can constrain gravitational noise temperature.

The model predicts measurable decoherence effects in near-future quantum optical experiments.

Gravitational decoherence could be significant for ultra-relativistic quantum systems.

Abstract

Models of gravitational decoherence are not commonly applied to ultra-relativistic systems, including photons. As a result, few quantum optical tests of gravitational decoherence have been developed. In this paper, we generalize the gravitational decoherence model of Anastopoulos and Hu (arXiv:1305.5231) to photons. In this model, decoherence originates from a bath of stochastic gravitational perturbations, possibly of fundamental origin. We derive a master equation for general states of the electromagnetic (EM) field; the only free parameter is a noise temperature $\Theta$ of the gravitational fluctuations. We find that interference experiments with long baselines, accessible in near-future experiments, can, in principle, lead to strong constraints in $\Theta$.