Single-shot single-mode optical two-parameter displacement estimation beyond classical limit

TL;DR

This paper demonstrates experimentally that non-Gaussian single-photon states can surpass the classical limit in estimating both components of displacement parameters in phase space within a single-shot, single-mode optical setup.

Contribution

It provides the first experimental validation of beating the classical limit for two-parameter displacement estimation using non-Gaussian states.

Findings

Successfully beat the classical limit in displacement estimation

First experiment estimating both parameters with non-Gaussian states

Potential applications in quantum error correction

Abstract

Uncertainty principle prohibits the precise measurement of both components of displacement parameters in phase space. We have theoretically shown that this limit can be beaten using single-photon states, in a single-shot and single-mode setting [F. Hanamura et al., Phys. Rev. A 104, 062601 (2021)]. In this paper, we validate this by experimentally beating the classical limit. In optics, this is the first experiment to estimate both parameters of displacement using non-Gaussian states. This result is related to many important applications, such as quantum error correction.