Thermal Quantum Discord in Anisotropic Heisenberg XXZ Model with Dzyaloshinskii-Moriya Interaction

• Published in: Communications in theoretical physics Vol. 54; no. 7; pp. 60 - 66
• Main Author: 陈一新 尹志
• Format: Journal Article
• Language: English
• Published: IOP Publishing 15.07.2010
• Subjects: 交互系统; 可调参数; 各向异性; 海森堡; 热纠缠; 相互作用; 量子模型; 量子点
• ISSN: 0253-6102
• DOI: 10.1088/0253-6102/54/1/12

The thermal quantum discord （QD） is studied in a two-qubit Heisenberg XXZ system with DzyaloshinskiiMoriya （DM） interaction. We compare the thermal QD with thermal entanglement in this system and find remarkable differences between them. For instance, we show situations where QD decreases asymptotically to zero with temperature T while entanglement decreases to zero at the point of critical temperature, situations where QD decreases with certain tunable parameters such as Dx and Dx when entanglement increases. We find that the characteristic of QD is exotic in this system and this possibly offers a potential solution to enhance entanglement of a system. We also show that tunable parameter Dx is more efficient than parameter Dz in most regions for controlling the QD.