Physical interpretation of nonlocal quantum correlation through local description of subsystems

TL;DR

This paper offers a physical interpretation of nonlocal quantum correlations by linking them to the lack of complete local descriptions, and demonstrates experimental discrimination of different quantum correlations using local uncertainty relations.

Contribution

It introduces a novel physical interpretation of nonlocal quantum correlations based on local uncertainty relations and provides an experimental method to distinguish various quantum correlations.

Findings

Nonlocal quantum correlations can be characterized by local uncertainty relations.

Different quantum correlations are distinguishable using a single uncertainty relation.

Experimental characterization of Werner states confirms the theoretical framework.

Abstract

Characterization and categorization of quantum correlations are both fundamentally and practically important in quantum information science. Although quantum correlations such as non-separability, steerability, and non-locality can be characterized by different theoretical models in different scenarios with either known (trusted) or unknown (untrusted) knowledge of the associated systems, such characterization sometimes lacks unambiguous to experimentalist. In this work, we propose the physical interpretation of nonlocal quantum correlation between two systems. In the absence of {\it complete local description} of one of the subsystems quantified by the {\it local uncertainty relation}, the correlation between subsystems becomes nonlocal. Remarkably, different nonlocal quantum correlations can be discriminated from a single uncertainty relation derived under local hidden state (LHS)-LHS model only. We experimentally characterize the two-qubit Werner state in different scenarios.