Noisy certification of continuous variables graph states

TL;DR

This paper develops practical methods for certifying continuous variables graph states in noisy, real-world conditions, enabling their reliable use in quantum communication, computing, and sensing.

Contribution

It adapts existing certification protocols to realistic scenarios, allowing efficient verification of CV graph states under noise and imperfections.

Findings

CV graph states can be certified in noisy environments

Protocols are applicable for quantum teleportation, computing, and sensing

Certification remains effective despite measurement and squeezing limitations

Abstract

Continuous variables (CV) offer a promising platform for the development of various applications, such as quantum communication, computing, and sensing, and CV graph states represent a family of powerful entangled resource states for all these areas. In many of these protocols, a crucial aspect is the certification of the quantum state subsequently used. While numerous protocols exist, most rely on assumptions unrealistic for physical continuous variable states, such as infinite precision in quadrature measurement or the use of states requiring infinite squeezing. In this work, we adapt existing protocols to deal with these unavoidable considerations, and use them to certify their application for different quantum information tasks. More specifically, we show how CV graph states can be efficiently verified and certified even in a noisy and imperfect setting. We then discuss how our findings impact the usability of states obtained after the protocol for different applications, including quantum teleportation, computing, and sensing.