Engineering Gaussian states of light from a planar microcavity

TL;DR

This paper demonstrates how to significantly amplify antibunching signals in quantum fluids of light from a microcavity using free-space optics, enabling better control and measurement of quantum correlations.

Contribution

It introduces an optical scheme to enhance antibunching signals in microcavity-generated quantum light and analyzes the output state as an approximate Gaussian state.

Findings

Antibunching signals can be amplified by orders of magnitude.

The Gaussian output state explains the antibunching behavior.

Spatial and temporal correlations can be reconstructed and enhanced.

Abstract

Quantum fluids of light in a nonlinear planar microcavity can exhibit antibunched photon statistics at short distances due to repulsive polariton interactions. We show that, despite the weakness of the nonlinearity, the antibunching signal can be amplified orders of magnitude with an appropriate free-space optics scheme to select and interfere output modes. Our results are understood from the unconventional photon blockade perspective by analyzing the approximate Gaussian output state of the microcavity. In a second part, we illustrate how the temporal and spatial profile of the density-density correlation function of a fluid of light can be reconstructed with free-space optics. Also here the nontrivial (anti)bunching signal can be amplified significantly by shaping the light emitted by the microcavity.