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The connection between quantum entanglement and quantum refrigerators is an active area in quantum thermodynamics. Ongoing investigations are exploring how entanglement in the working medium of a quantum refrigerator can impact its performance. The paper focuses on a two-qubit Heisenberg XXZ spin-$\frac{1}{2}$ system featuring Kaplan–Shekhtman–Entin-Wohlman–Aharony (KSEA) and Dzyaloshinsky–Moriya (DM) spin–orbit exchange interactions as the operational physical matter medium for a quantum refrigerator. We provide explicit formulations for relevant thermodynamic quantities of the quantum refrigerator, dependent on the magnetic field (B) and the strengths parameters of spin–orbit interactions. The study explores the relationship between entanglement and thermodynamic properties, using concurrence as a quantitative metric of thermal entanglement. The results emphasize the significant impact of fine-tuning the amplitudes of both DM and $KSEA$ strengths on improving the quantum refrigerator’s performance. Finally, the findings suggest that entanglement between the qubits is superfluous for enhancing the quantum refrigerator’s efficiency.

In the present paper, an influence of the anisotropic antisymmetric exchange interaction, the Dzialoshinskii–Moriya (DM) interaction, on entanglement of two qubits in various magnetic spin models, including the pure DM model and the most general XYZ model, are studied. We find that the time evolution generated by DM interaction can implement the SWAP gate and discuss realistic quasi-one-dimensional magnets where it can be realized. It is shown that inclusion of the DM interaction to any Heisenberg model creates, when it does not exist, or strengthens, when it exists, the entanglement. We give physical explanation of these results by studying the ground state of the systems at T = 0. Nonanalytic dependence of the concurrence on the DM interaction and its relation with quantum phase transition is indicated. Our results show that spin models with the DM coupling have some potential applications in quantum computations and the DM interaction could be an efficient control parameter of entanglement.

In this paper, we use the negativity and geometric quantum discord (GQD) to investigate the quantum phase transition (QPT) in the anisotropic spin-1/2 XY model with staggered Dzyaloshinskii–Moriya (DM) interaction using the quantum renormalization-group method, and the results show that the negativity and GQD can both obtain the quantum critical points associated with QPTs after several iterations of the renormalization. In addition to this, we discuss how the strength of the DM interaction and anisotropic parameter make the effect on the negativity and GQD for different RG steps. At last, we give out the relationship between negativity and GQD, and verify that with anisotropy parameter and the strength of DM interaction increased, the squared negativity and the normalization of GQD tend to equal in this model.

Thermal entanglement of a two-qubit Heisenberg XXZ chain in the presence of different Dzyaloshinskii–Moriya (DM) anisotropic antisymmetric interactions and entanglement teleportation using two independent Heisenberg chains as quantum channel are investigated. It is found that the anisotropic coupling coefficient J_z (z-component exchange constant) and DM interactions can excite the entanglement, and x-component DM interaction D_x has a more remarkable influence than the z-axis DM interaction D_z for exchange constant J > 0 (antiferromagnetic) case, which is contrary to coupling coefficient J < 0 (ferromagnetic) case. The output entanglement and fidelity increase with increasing z-axis coupling parameter J_z for both the antiferromagnetic J > 0 case and ferromagnetic J < 0 case. By introducing the different DM interactions, it is superior to teleportate initial state by using the D_z interaction in the model for J > 0 case. But for J < 0 case, the D_x interaction is better, and the output concurrence and fidelity can reach the maximum value 1 with suitable D_x.

The quantum teleportation via thermally entangled states of three-qubit Heisenberg spin chains with Dzyaloshinsky–Moriya (DM) interactions under a homogeneous magnetic field has been investigated. It is found that average fidelity and critical temperature depend on not only temperature, magnetic field, but also coupling coefficients, and DM interactions. What is more, we also find that average fidelity has little to do with entanglement.

In this paper, we study the thermal entanglement in a two-qubit Heisenberg XYZ system with different Dzyaloshinskii–Moriya (DM) couplings. We show that different DM coupling parameters have different influences on the entanglement and the critical temperature. In addition, we find that when J_i (i-component spin coupling interaction) is the largest spin coupling coefficient, D_i (i-component DM interaction) is the most efficient DM control parameter, which can be obtained by adjusting the direction of DM interaction.

The effect of Dzialoshiski-Moriya (DM) interaction and anisotropy on the thermal entanglement of a two-qutrit XXZ spin chain is investigated. Our analysis implies that the DM interaction and weak anisotropy can enhance the thermal entanglement to a maximum value while the strong anisotropy plays a positive role in shrinking thermal entanglement. Furthermore, we find that the entanglement evolution in terms of anisotropy is sensitive to weak anisotropy.

We have studied the symmetric and non-symmetric pairwise ground state and thermal entanglement in three-qubits system. We have considered the anisotropic Heisenberg (XXZ) model in the presence of Dzyaloshinskii–Moriya (DM) interaction in addition to the Ising model in a magnetic field with DM interaction. We have found that the increment of DM interaction and magnetic field can enhance and reduce the entanglement of the system. We have shown that the non-symmetric pairwise state has higher value concurrence and critical temperature (above which the entanglement vanishes) than the symmetric pairwise one. For the negative anisotropy, the non-symmetric entanglement is a monotonic function of DM interaction while for positive anisotropy, it has a maximum versus DM parameter and vanishes for larger values of DM interaction. The conditions for the existence of thermal entanglement are discussed in detail. The most remarkable result appears at zero temperature where the three-qubits ground state entanglement of the system (in spite of two-qubits counterpart) shows the fingerprint of the quantum phase transition for a system of infinite number of qubits.

We have investigated the quantum discord (QD) of the thermal density matrix of spin-1/2 Heisenberg chains with Dzyaloshinskii–Moriya (DM) interaction. With fermionization technique, we study the mutual effect of DM interaction and the external magnetic field on the QD and the entanglement. Our analysis implies that the DM interaction can enhance the QD while the external magnetic field will shrink the QD. By a comparison between the entanglement and the QD, we find that the QD is more robust to the temperature and to the external magnetic field than the entanglement of formation (EoF) in the sense that the EoF takes a zero value while the QD does not for high temperature and strong external magnetic field. This point confirms the conclusion that there exist some separable states containing non-zero QD.