One-way quantum deficit for $2\otimes d$ systems

TL;DR

This paper analyzes the one-way quantum deficit in 2×d quantum systems, providing analytical formulas, exploring its behavior under different measurements, and studying its dynamics under dephasing channels, with a focus on qubit-qutrit systems.

Contribution

It offers the first analytical expressions for one-way quantum deficit under von Neumann and weak measurements in 2×d systems, and examines their dynamics under dephasing.

Findings

Non-zero quantum deficit exists even when entanglement vanishes.

Weak measurement yields a weaker quantum deficit than von Neumann measurement.

Quantum deficit dynamics under dephasing channels are characterized.

Abstract

We investigate one-way quantum deficit for $2\otimes d$ systems. Analytical expressions of one-way quantum deficit under both von Neumann measurement and weak measurement are presented. As an illustration, qubit-qutrit systems are studied in detail. It is shown that there exists non-zero one-way quantum deficit even quantum entanglement vanishes. Moreover, one-way quantum deficit via weak measurement turns out to be weaker than that via von Neumann measurement. The dynamics of entanglement and one-way quantum deficit under dephasing channels is also investigated.