Scaling of multicopy constructive interference of Gaussian states

TL;DR

This paper investigates how the constructive interference of multiplexed nonclassical Gaussian states scales in multimode bosonic systems, providing theoretical predictions and introducing a gain-to-instability ratio for assessing resource stability.

Contribution

It introduces new scaling laws for Gaussian state interference and a gain-to-instability ratio to evaluate resource stability in large-scale quantum interference architectures.

Findings

Scaling laws for constructive interference of Gaussian states are predicted.

The gain-to-instability ratio quantifies resource stability and potential for large-scale implementation.

Framework facilitates future experimental verification and theoretical exploration.

Abstract

Quantum technology advances crucially depend on the scaling up of essential quantum resources. Their ideal multiplexing offers more significant gains in applications; however, the scaling of the nonidentical, fragile and varying resources is neither theoretically nor experimentally known. For bosonic systems, multimode interference is an essential tool already widely exploited to develop quantum technology. Here, we analyze, predict and compare essential scaling laws for a constructive interference of multiplexed nonclassical Gaussian states carrying information by displacement with weakly fluctuating squeezing in different multimode interference architectures. The signal-to-noise ratio quantifies the increase in displacement relative to the noise. We introduce the gain-to-instability ratio to numerically estimate the effect of unexplored resource instabilities in a large scale interference scheme. The use of the gain-to-instability ratio to quantify the scaling laws opens steps for extensive theoretical investigation of other bosonic resources and follow-up feasible experimental verification necessary for further development of these platforms.