Characterizing the Multipartite Entanglement Structure of Non-Gaussian Continuous-Variable States with a Single Evolution Operator

TL;DR

This paper presents a new efficient method using quantum Fisher information to detect and characterize multipartite entanglement in non-Gaussian continuous-variable quantum states, applicable to a wide range of systems.

Contribution

It introduces a systematic approach to identify optimal encoding operators for capturing quantum correlations in multimode non-Gaussian states, improving entanglement detection robustness.

Findings

High success rate in detecting entanglement in over 10^5 states

Enhanced robustness against losses by expanding operator sets

Provides a general framework for diverse continuous variable systems

Abstract

Multipartite entanglement is an essential resource for quantum information tasks, but characterizing entanglement structures in continuous variable systems remains challenging, especially in multimode non-Gaussian scenarios. In this work, we introduce an efficient method for detecting multipartite entanglement structures in continuous-variable states. Based on the quantum Fisher information, we propose a systematic approach to identify an optimal encoding operator that can capture the quantum correlations in multimode non-Gaussian states. We demonstrate the effectiveness of our method on over $10^5$ randomly generated multimode-entangled quantum states, achieving a very high success rate in entanglement detection. Additionally, the robustness of our method can be considerably enhanced against losses by expanding the set of accessible operators. This work provides a general framework for characterizing entanglement structures in diverse continuous variable systems, enabling a number of experimentally relevant applications.