Nonlinear Michelson interferometer for improved quantum metrology

TL;DR

This paper explores a nonlinear Michelson interferometer using Kerr nonlinearity and classical pulses, highlighting how nonlinearity introduces pulse duration as a new variable affecting quantum measurement limits.

Contribution

It introduces a nonlinear interferometer with Kerr nonlinearity for quantum metrology, emphasizing the role of pulse duration alongside energy resources.

Findings

Nonlinear interferometer improves robustness against imperfections.

Pulse duration becomes a key variable in quantum limits.

Nonlinearity enhances quantum measurement capabilities.

Abstract

We examine quantum detection via a Michelson interferometer embedded in a gas with Kerr nonlinearity. This nonlinear interferometer is illuminated by pulses of classical light. This strategy combines the robustness against practical imperfections of classical light with the improvement provided by nonlinear processes. Regarding ultimate quantum limits, we stress that, as a difference with linear schemes, the nonlinearity introduces pulse duration as a new variable into play along with the energy resources.