Phase estimation of Mach-Zehnder interferometer via Laguerre excitation squeezed state

TL;DR

This paper investigates phase estimation in a Mach-Zehnder interferometer using Laguerre excitation squeezed states, analyzing the impact of losses and demonstrating potential improvements over traditional states in realistic conditions.

Contribution

Introduces Laguerre excitation squeezed states as input for phase estimation, analyzing their robustness and advantages under realistic loss conditions.

Findings

External loss has a greater impact than internal loss.

Phase sensitivity can be enhanced by increasing photon number.

Laguerre excitation squeezed states can surpass ideal phase sensitivity in certain conditions.

Abstract

Quantum metrology has an important role in the fields of quantum optics and quantum information processing. Here we introduce a kind of non-Gaussian state, Laguerre excitation squeezed state as input of traditional Mach-Zehnder interferometer to examine phase estimation in realistic case. We consider the effects of both internal and external losses on phase estimation by using quantum Fisher information and parity detection. It is shown that the external loss presents a bigger effect than the internal one. The phase sensitivity and the quantum Fisher information can be improved by increasing the photon number and even surpass the ideal phase sensitivity by two-mode squeezed vacuum in a certain region of phase shift for realistic case.