Two-mode Gaussian product states in a Lossy Interferometer

TL;DR

This paper analyzes the quantum Fisher information of two-mode Gaussian product states in a lossy interferometer, deriving bounds on phase estimation precision and comparing scaling behaviors with other quantum states.

Contribution

It provides the quantum Cramer-Rao bound for phase estimation using two-mode Gaussian product states under photon loss, highlighting their measurement precision limits.

Findings

Quantum Fisher information bounds for lossy interferometers

Comparison of measurement precision scaling with dual squeezed vacuum states

Insights into phase estimation limits with Gaussian product states

Abstract

The quantum Fisher information for a two-mode, Gaussian product state in an interferometer subject to photon loss is studied. We obtain the quantum Cramer-Rao bound on the achievable precision in phase estimation using such states. The scaling of the measurement precision with the mean photon number for such input product states is compared to the limited scaling for dual squeezed vacuum states and for dual squeezed, displaced vacuum states.