Quantum steering in a star network

¹ College of Physical Science and Technology, Sichuan University - Chengdu 610064, China
² Quantum Optoelectronics Laboratory, School of Physical Science and Technology, Southwest Jiaotong University Chengdu 610031, China
³ Department of Applied Physics, School of Physical Science and Technology, Southwest Jiaotong University Chengdu 611756, China

Received: 8 November 2023
Accepted: 23 May 2024

Abstract

In this work, we will consider the star network scenario where the central party is trusted while all the edge parties (with a number of n) are untrusted. Network steering is defined with an n local hidden state model which can be viewed as a special kind of n local hidden variable model. Two different types of sufficient criteria, nonlinear steering inequality and linear steering inequality will be constructed to verify the quantum steering in a star network. Based on the linear steering inequality, how to detect the network steering with a fixed measurement will be discussed.