Influence of magnetic current on the ground state entanglement in an isotropic transverse XY chain  

作　　者：Liu Dan Zhang Yong Long Guilu 

机构地区：[1]Key Laboratory for Atomic and Molecular NanoSciences, and Department of Physics, Tsinghua University, Beijing 100084, China [2]Center of Quantum Information Science and Technology, Tsinghua National Laboratory for information Science and Technology, Beijing 100084, China [3]Institute of Physics, School of Sciences, Beijing University of Posts and Telecommunications, Beijing 100876, China

出　　处：《Progress in Natural Science:Materials International》2007年第10期1147-1151,共5页自然科学进展·国际材料（英文版）

基　　金：Supported by National Natural Science Foundation of China (Grant Nos 10447116 ,10325521 ,60433050 &60635040)

摘　　要：We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ>3, namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ〉/3, namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.

关 键 词：Heisenberg-XY chain magnetic-current phase transition. 

分 类 号：O561[理学—原子与分子物理]