Two-colour spectrally multimode integrated SU(1,1) interferometer

TL;DR

This paper proposes a novel integrated multimode two-colour SU(1,1) interferometer that suppresses dispersion, enhances interference visibility, and surpasses classical phase sensitivity limits for high photon numbers, advancing quantum metrology.

Contribution

The paper introduces a theoretically designed integrated multimode two-colour SU(1,1) interferometer that overcomes dispersion issues and achieves supersensitive operation.

Findings

Suppresses dispersion to improve interference visibility

Overcomes classical phase sensitivity limit at high photon numbers

Operates effectively in a wide parametric gain range

Abstract

Multimode integrated interferometers have great potential for both spectral engineering and metrological applications. However, material dispersion of integrated platforms constitutes an obstacle which limits the performance and precision of such interferometers. At the same time, two-colour non-linear interferometers present an important tool for metrological applications, when measurements in a certain frequency range are difficult. In this manuscript, we theoretically develop and investigate an integrated multimode two-colour SU(1,1) interferometer that operates in a supersensitive mode. By ensuring a proper design of the integrated platform, we suppress dispersion and thereby significantly increase the visibility of the interference pattern. We demonstrate that such an interferometer overcomes the classical phase sensitivity limit for wide parametric gain ranges, when up to $3*10^4$ photons are generated.