Probing quantum entanglement, quantum discord, classical correlation, and the quantum state without disturbing them

TL;DR

This paper introduces cavity QED-based schemes to probe quantum entanglement, discord, and classical correlation in bipartite states without disturbance, analyzing the effects of spontaneous emission on detection accuracy.

Contribution

It presents novel non-invasive probing methods for quantum correlations using cavity QED, preserving the measured quantities during detection.

Findings

Detection does not influence quantum correlations

Spontaneous emission impacts detection accuracy

Proposed schemes are feasible with current cavity QED technology

Abstract

In this paper, we present schemes for a type of one-parameter bipartite quantum states to probe the quantum entanglement, the quantum discord, the classical correlation and the quantum state based on the cavity QED. It is shown that our detection does not influence all these measured quantities. We also discuss how the spontaneous emission introduced by our probe atom influences our detection.