Quantum coherence quantifiers based on the R\'{e}nyi $\alpha$-relative entropy

TL;DR

This paper investigates the properties of quantum coherence measures based on Rényi α-relative entropy, revealing limitations in their monotonicity and exploring their trade-offs with mixedness, especially for single qubits.

Contribution

It demonstrates that Rényi α-relative entropy of coherence generally lacks monotonicity and analyzes its implications and properties for single qubits.

Findings

Rényi α-relative entropy of coherence does not satisfy monotonicity under subselection of measurements.

It also fails to meet the extended monotonicity requirement.

Trade-off relations between coherence and mixedness are established.

Abstract

The resource theories of quantum coherence attract a lot of attention in recent years. Especially, the monotonicity property plays a crucial role here. In this paper we investigate the monotonicity property for the coherence measures induced by the R\'{e}nyi $\alpha$-relative entropy which present in [Phys. Rev. A 94, 052336, 2016]. We show that the R\'{e}nyi $\alpha$-relative entropy of coherence does not in general satisfy the monotonicity requirement under the subselection of measurements condition and it also does not satisfy the extension of monotonicity requirement which presents in [Phys. Rev. A 93, 032136, 2016]. Due to the R\'{e}nyi $\alpha$-relative entropy of coherence can act as a coherence monotone quantifier, we examine the trade-off relations between coherence and mixedness. Finally, some properties for the single qubit of R\'{e}nyi $2$-relative entropy of coherence are derived.