Entangled quantum fridge using a two spin-12 Heisenberg system with Dzyaloshinskii–Moriya and Kaplan–Shekhtman–Entin-Wohlman–Aharony interactions as a working medium
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-[Formula: see text] 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 [Formula: see text] 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.
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-[Formula: see text] 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 [Formula: see text] 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.
This paper explores thermal quantum memory-assisted entropic uncertainty, Bell-non-locality, and entanglement in a two-qubit Heisenberg XXX chain with x-directional Dzyaloshinskii-Moriya (DM) and Kaplan-Shekhtman-Entin-Wohlman-Aharony (KSEA) interactions in thermal equilibrium. We find this crucial that the initial degree of nonlocality and entanglement in the two-qubit state entirely depends upon the temperature, orientation, and strength of the DM and KSEA interaction of the magnetic field. Among many other situations, the magnetic field characterized by DM interaction with minimal temperature, exchange coupling strength, and KSEA interaction is the most reliable for generating and maintaining maximal nonlocality and entanglement while completely suppressing entropic uncertainty. On the other hand, repeated revivals and non-Markovian dynamics have been observed when the magnetic field is characterized by exchange coupling constant, DM and KSEA interaction with a higher temperature limit. Except for temperature-based magnetic fields, we show that maximal entanglement and nonlocality are generated and preserved in the two qubits with zero-order entropic uncertainty, which we believe is a better result than previous studies.
Quantum entanglement is one of the most important measures of quantum correlations. Using group-theoretical approach we found a family of four nine-parameter quantum states for the two-spin-1/2 Heisenberg system in an external magnetic field and with multiple components of Dzyaloshinsky-Moriya (DM) and Kaplan-Shekhtman- Entin-Wohlman-Aharony (KSEA) interactions. Exact analytical formulas are derived for the entanglement of formation for the quantum states found. In the proceeding, the family of found states and the structure of interactions in them are discussed.
Abstract In this study, the quantum-memory assisted entropic uncertainty (QM-EU) and entanglement dynamics of the two-qubit Heisenberg XXX chain have been explored in the presence of intrinsic decoherence. The effect of the x-component of Dzyaloshinskii-Moriya (DM) and Kaplan-Shekhtman-Entin-Wohlman-Aharony (KSEA) interactions has been considered. The generation and preservation of quantum memory and entanglement have been examined for various values of the DM, KSEA, spin-spin, and spin coupling strengths. The uncertainty negatively affects the entanglement and both have anti-correlation. The absence and presence of intrinsic decoherence prevail in differing impacts on the dynamics of the system. In the first case, prolonged entanglement preservation, uncertainty suppression, and oscillatory dynamics have been observed. Moreover, in order to achieve the best-prolonged entanglement preservation and relative reduction of the entropic uncertainty, we have analyzed several parameter settings. We find that the effects of raising the DM, KSEA, and spin-spin interaction individually and simultaneously are different. The individual and simultaneous increase of the DM, KSEA, and spin-spin interaction parameters control the degree of entanglement, entropic uncertainty, and primarily the dynamics of the system.
Based on an isotropic two spin-1/2 qubits Heisenberg model with the Dzyaloshinskii—Moriya interaction in an external magnetic field, we have constructed an entangled quantum refrigerator. Expressions for the basic thermodynamic quantities, i.e., the heat exchanged, the net work input, and the coefficient of performance, are derived. Some intriguing features and their qualitative explanations in zero and non zero magnetic fields are given. The influence of the thermal entanglement on the refrigerator is investigated. The results obtained here have general significance and will be helpful to understand the performance of an entangled quantum refrigerator.
Abstract This study explores the spontaneous emergence of local Fisher information and local quantum uncertainty beyond entanglement in a noisy two-qubit Heisenberg XXX model with Dzyaloshinskii-Moria (DM) and Kaplan-Shekhtman-Entin-Wohlman-Aharony (KSEA) interactions. Local quantum Fisher information, local quantum uncertainty, and logarithmic negativity are used to examine two-spin non-locality. We find that by employing strong two-spin, Dzyaloshinskii- Moriya, and Kaplan-Shekhtman-Entin-Wohlman-Aharony interactions, we can prevent noise-induced losses in local Fisher information, local quantum uncertainty, and logarithmic negativity. The robustness of the two-spin non-localities is greater for a strong spin’s coupling strength than for the strong DM and KSEA interactions. Local Fisher information and local quantum uncertainty, as well as logarithmic-negativity, display asymmetric behaviors with respect to two-spin coupling and symmetric behaviors with respect to the Dzyaloshinskii-Moriya and Kaplan-Shekhtman-Entin-Wohlman-Aharony interactions. At high bath temperatures, the phenomenon of sudden-death two-spin entanglement emerges. Furthermore, by combining the parameters of the strong two-spin, DM, and KSEA interactions, the robustness of the produced two-spin non-localities can be improved.
Abstract We employ entanglement negativity, local quantum uncertainty (LQU), and local quantum Fisher information (LQFI) to characterize thermal entanglement between two XYZ-Heisenberg-qubit states under the influence of Dzyaloshinsky-Moriya(DM) and Kaplan-Shekhtman-Entin-Wohlman-Aharony (KSEA) interactions, as well as a magnetic field and thermal equilibrium temperature. A comparative examination reveals similar behaviors among these correlation measures. For the antiferromagnetic scenario, we observe that increasing the DM interaction parameter D z enhances thermal entanglement. Conversely, in the ferromagnetic case, the behavior of thermal entanglement differs with varying D z . Additionally, employing Kraus operators, we explore the performance of these quantifiers under decoherence. Notably, LQFI exhibits greater robustness than negativity and LQU, even displaying a frozen phenomenon at some time under dephasing effects.