Quantum Discord: A Dynamic Approach in Geometric Picture

TL;DR

This paper introduces a dynamic method to evaluate quantum discord using local filtering, linking it to quantum channels and capacities, and replacing traditional measurement optimization with a more rigorous POVM approach.

Contribution

It proposes a novel dynamic framework for quantum discord evaluation that improves accuracy by utilizing three-element POVMs instead of von Neumann measurements.

Findings

More precise quantum discord calculations achieved.

Reveals connection between quantum discord and channel capacity.

Provides a new measurement optimization technique.

Abstract

We present a dynamic approach to study the quantum discord and classical correlation. By local filtering operation, the evaluation of quantum discord is closely related to quantum channel and channel capacity. As a consequence, the traditional optimization over horizontal-or-vertical von Neumann measurements is replaced by that over horizontal-and-vertical three-element POVM measurement, from which more rigorous results of quantum discord are obtained.