Remote Phase Sensing by Coherent Single Photon Addition

TL;DR

This paper introduces a remote phase sensing method leveraging entanglement from coherent multimode photon addition, enabling high-sensitivity phase estimation remotely without direct interaction with the sample.

Contribution

It presents a novel remote phase sensing scheme based on coherent multimode photon addition and derives the optimal measurement for phase estimation.

Findings

Sensitivity scales with the intensity of local coherent states

Experimental validation confirms the theoretical predictions

Method enables remote phase estimation without direct sample interaction

Abstract

We propose a remote phase sensing scheme inspired by the high sensitivity of the entanglement produced by coherent multimode photon addition on the phase set in the remote heralding apparatus. By exploring the case of delocalized photon addition over two modes containing identical coherent states, we derive the optimal observable to perform remote phase estimation from heralded quadrature measurements. The technique is experimentally tested with calibration measurements and then used for estimating a remote phase with a sensitivity that is found to scale with the intensity of the (local) coherent states, which never interacted with the sample.