Optimal non-Gaussian operations in difference-intensity detection and parity detection-based Mach-Zehnder interferometer

TL;DR

This paper explores how probabilistic non-Gaussian operations like photon subtraction, addition, and catalysis can optimize phase estimation in Mach-Zehnder interferometers with difference-intensity and parity detection, providing practical parameters for experimental implementation.

Contribution

It identifies the most effective non-Gaussian operations for each detection scheme and derives a general moment-generating function useful for various detection methods.

Findings

Photon catalysis is optimal for difference-intensity detection-based MZI.

Photon addition is optimal for parity detection-based MZI.

The study provides specific squeezing and transmissivity parameters for best performance.

Abstract

We investigate the benefits of probabilistic non-Gaussian operations in phase estimation using difference-intensity and parity detection-based Mach-Zehnder interferometers (MZI). We consider an experimentally implementable model to perform three different non-Gaussian operations, namely photon subtraction (PS), photon addition (PA), and photon catalysis (PC) on a single-mode squeezed vacuum (SSV) state. In difference-intensity detection-based MZI, two PC operation is found to be the most optimal, while for parity detection-based MZI, two PA operation emerges as the most optimal process. We have also provided the corresponding squeezing and transmissivity parameters at best performance, making our study relevant for experimentalists. Further, we have derived the general expression of moment-generating function, which shall be useful in exploring other detection schemes such as homodyne detection and quadratic homodyne detection.