Heisenberg-limited quantum interferometry with multi-photon subtracted twin beams

TL;DR

This paper introduces a quantum interferometer utilizing photon-subtracted twin beams to achieve Heisenberg-limited sensitivity with direct fringe readout, supported by feasible experimental design and realistic loss analysis.

Contribution

It presents a novel interferometer design with photon subtraction that attains Heisenberg-limited precision and allows direct fringe measurement, improving upon previous twin-beam schemes.

Findings

Achieves Heisenberg-limited phase sensitivity.

Demonstrates feasibility with non-degenerate parametric down-conversion.

Analyzes performance under realistic loss and detector inefficiencies.

Abstract

We propose a Heisenberg-limited quantum interferometer whose input is twin optical beams from which one or more photons have been indistinguishably subtracted. Such an interferometer can yield Heisenberg-limited performance while at the same time giving a direct fringe reading, unlike for the twin-beam input of the Holland-Burnett interferometer. We propose a feasible experimental realization using a photon-number correlated source, such as non-degenerate parametric down-conversion, and perform realistic analyses of performance in the presence of loss and detector inefficiency.