By using the non-Markovian Quantum State Diffusion method, the non-Markovian dynamics of entanglement, quantum dense coding and quantum teleportation in the spin chain system with Kaplan-Shekhtman-Entin-wohlman-Aharony interactions and Dzyaloshinskii-Moriya interactions are studied. In particular, the joint effects of Kaplan-Shekhtman-Entin-wohlmanAharony interactions and different external magnetic fields are discussed under zero and finite temperatures, respectively. The results show that the concurrence, channel capacity of quantum dense coding and average fidelity of quantum teleportation can be effectively increased via the increasing of Kaplan-Shekhtman-Entin-wohlman-Aharony interactions along the z-direction which can be attributed to the constructive role of Kaplan-Shekhtman-Entin-wohlman-Aharony interactions on the O(3) invariance in the spin chain. Non-uniform magnetic fields with the combination of Kaplan-Shekhtman-Entin-wohlman-Aharony interactions are found to be more effective in the increasing of the parameters unfer discussion.
By using the non-Markovian Quantum State Diffusion method, the non-Markovian dynamics of entanglement, quantum dense coding and quantum teleportation in the spin chain system with Kaplan-Shekhtman-Entin-wohlman-Aharony interactions and Dzyaloshinskii-Moriya interactions are studied. In particular, the joint effects of Kaplan-Shekhtman-Entin-wohlmanAharony interactions and different external magnetic fields are discussed under zero and finite temperatures, respectively. The results show that the concurrence, channel capacity of quantum dense coding and average fidelity of quantum teleportation can be effectively increased via the increasing of Kaplan-Shekhtman-Entin-wohlman-Aharony interactions along the z-direction which can be attributed to the constructive role of Kaplan-Shekhtman-Entin-wohlman-Aharony interactions on the O(3) invariance in the spin chain. Non-uniform magnetic fields with the combination of Kaplan-Shekhtman-Entin-wohlman-Aharony interactions are found to be more effective in the increasing of the parameters unfer discussion.
Since the discovery of symmetric helical interactions in the spin-orbit coupled single-band Hubbard model by Moriya and Kaplan, Shekhtman, Entin, Aharony et al. have successfully used this non-negligible symmetric helical exchange interaction to explain the weak ferromagnetism of La2CuO4. By using the non-Markovian quantum state diffusion method, the quantum discord of non-Markovian dynamics in the spin chain system that has Kaplan–Shekhtman–Entin-Wohlman–Aharony interactions and Dzyaloshinskii-Moriya interactions is studied. The effects of Kaplan–Shekhtman–Entin-Wohlman–Aharony interaction on the quantum discord under different external magnetic fields at zero and finite temperatures are discussed. The results show that the quantum discord in the system can be increased via the increasing of Kaplan–Shekhtman–Entin-Wohlman–Aharony interaction in the case of zero or uniform magnetic field, while the case is opposite under the nonuniform magnetic field. More importantly, the ideal discord state can be obtained by modulating the uniform magnetic field and Kaplan–Shekhtman–Entin-Wohlman–Aharony interaction. Moreover, the Markovian case and the effect of temperature on the quantum discord are also discussed, respectively.
One of the teleportation versions is applied to convey an entangled two-qubit system via a class of a two-qubit XYZ Heisenberg chain model. At thermal equilibrium, the exact solution of the XYZ model with an external magnetic field and the Kaplan-Shekhtman-Entin-Wohlman-Aharony interaction (KSEWA-interaction) is proposed in X, and Z direction. The teleported quantum Fisher information is studied, where we estimate the weight parameter θ, temperature and the strength parameter of KSEWA-interaction. It is found that, the strength of the KSEWA-interaction and the magnetic field be of benefit in the case of estimating the weight function. Meanwhile, the temperature decreases the teleported information.
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.
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.
Abstract Quantum entanglement is a special nonlocal association between quantum systems. It is a fundamental feature of the difference between quantum and classical. At the same time, it acts as a very important resource in quantum informatics. Therefore, entanglement plays a noble role in quantum information and quantum computing. Quantum dense coding, as an application of quantum entanglement in practice, is a quantum communication protocol characterized by security and secrecy, which plays a very important role in quantum informatics and cryptography. This paper is mainly in the Non-Markovian environment of Heisenberg Spin chain system, using the quantum dense coding scheme proposed by Bennett et al. to study The dynamics of quantum dense coding channel capacity evolution with time and the entanglement dynamics of the system are discussed in detail.Based on the theoretical knowledge of open quantum systems and the maximum entangled state ∣ψAB⟩=21(∣11⟩+∣00⟩) as the initial state, the density matrix of the system evolution over time is obtained by quantum state diffusion method,and the evolution of channel capacity and entanglement over time of Heisenberg spin chains is simulated accurately. The results show that: the capacity and entanglement of dense coded channel oscillate with time and reach different stable values. Environmental correlation coefficientγand coupling strengthηand a play an important role in dense coding and quantum entanglement of quantum systems.Proper selection of parameters can keep the system good entanglement characteristics and increase the channel capacityχof the system, thus ensuring the effective transmission and processing of quantum information in practice. It lays a solid foundation for quantum computing
We investigate the effect of Calogero-Moser (CM) type interactions on the thermal entanglement and teleportation in an anisotropic two-qubit Heisenberg XYZ system with Dzyaloshinskii-Moriya (Dz) interaction in the presence of the external magnetic field. In this regard, the system is designed and analytically solved. The final state density of the system is obtained, and the impact of the system parameters is investigated. The negativity is used to quantify the entanglement dynamics over the system. The generated entangled channels are examined to exchange the information between the system qubits using the standard teleportation protocol; then, the fidelity of the transmitted information is quantified. The effect of the system parameters (Dzyaloshinskii-Moriya, Spin-orbit coupling, CM type interaction, and magnetic field) in the dynamics of the entanglement and state transfer is investigated. Our results indicate that the strength coupling, Dzyaloshinskii-Moriya (Dz) interaction, and magnetic field have a great effect on the dynamics of the entanglement and, consequently, the quality of the generated channels to exchange the information. In addition, we observe that the entanglement of sudden death exists when the distance between the spins is increased.