# Phase diagram for the one-way quantum deficit of two-qubit X states

@article{Yurischev2019PhaseDF, title={Phase diagram for the one-way quantum deficit of two-qubit X states}, author={Mikhail A. Yurischev}, journal={Quantum Information Processing}, year={2019}, volume={18}, pages={1-20} }

The one-way quantum deficit, a measure of quantum correlation, can exhibit for X quantum states the regions (subdomains) with the phases $$\varDelta _0$$Δ0 and $$\varDelta _{\pi /2}$$Δπ/2 which are characterized by constant (i.e., universal) optimal measurement angles, correspondingly, zero and $$\pi /2$$π/2 with respect to the z-axis and a third phase $$\varDelta _\vartheta $$Δϑ with the variable (state-dependent) optimal measurement angle $$\vartheta $$ϑ. We build the complete phase diagram…

## 7 Citations

On the possibility to detect quantum correlation regions with the variable optimal measurement angle

- PhysicsThe European Physical Journal D
- 2019

Abstract
Quantum correlations described by quantum discord and one-way quantum deficit can contain ordinary regions with constant (i.e., universal) optimal measurement angle 0 or π/2 with respect to…

Representations of two-qubit and ququart states via discrete Wigner functions

- Mathematics
- 2019

By means of a well-grounded mapping scheme linking Schwinger unitary operators and generators of the special unitary group $\mathrm{SU(N)}$, it is possible to establish a self-consistent theoretical…

Temperature-field phase diagrams of one-way quantum work deficit in two-qubit XXZ spin systems

- PhysicsQuantum Inf. Process.
- 2020

This model gives a complete classification of all qualitatively different phase diagrams for the one-way quantum work (information) deficit and found cases of phase diagrams in which the sizes of regions with the variable optimal measurement angle are large and perhaps such regions can be detected experimentally.

Jumps of optimal measurement angle and fractures on the curves of quantum correlation functions

- PhysicsInternational Conference on Micro- and Nano-Electronics
- 2019

The one-way quantum work deficit, a measure of quantum correlation, exhibits the regions with the bimodal behavior of post-measurement entropy versus the measurement angle θ ε (0, π/2). Under certain…

Landau-type sudden transitions of quantum correlations

- Physics
- 2022

Sudden changes of quantum correlations in the Bell-diagonal states are well-known effects. They occur when the set of optimal parameters that determine the quantum correlation consists of isolated…

On the quantum correlations in two-qubit XYZ spin chains with Dzyaloshinsky–Moriya and Kaplan–Shekhtman–Entin-Wohlman–Aharony interactions

- PhysicsQuantum Inf. Process.
- 2020

A group-theoretical approach finds fifteen spin Hamiltonians and as many corresponding Gibbs density matrices (quantum states) whose eigenvalues are expressed only through square radicals and shows that the remaining six quantum states are separable and that they are also connected by local unitary transformations.

Bifurcations and catastrophes at the boundaries separating the phases of quantum correlations

- PhysicsInternational Conference on Micro- and Nano-Electronics
- 2022

The spin-1/2 XXZ chain in a uniform magnetic field at thermal equilibrium is considered. For this model, we give phase diagrams for the one-way quantum work deficit (thermal discord). The diagrams…

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