中国物理B ›› 2008, Vol. 17 ›› Issue (11): 4002-4008.doi: 10.1088/1674-1056/17/11/011

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Entanglement and quantum phase transition in alternating XY spin chain with next-nearest neighbouring interactions

单传家, 程维文, 刘堂昆, 黄燕霞, 李宏   

  1. College of Physics and Electronic Science, Hubei Normal University, Huangshi 435002, China
  • 收稿日期:2008-05-11 修回日期:2008-05-29 出版日期:2008-11-20 发布日期:2008-11-20
  • 基金资助:
    Project supported by the Key Higher Education Program of Hubei Province, China (Grant No Z20052201), Natural Science Foundation of Hubei Province, China (Grant No 2006ABA055) and Postgraduate Program of Hubei Normal University of China (Grant No 2007D20) .

Entanglement and quantum phase transition in alternating XY spin chain with next-nearest neighbouring interactions

Shan Chuan-Jia (单传家), Cheng Wei-Wen (程维文), Liu Tang-Kun (刘堂昆), Huang Yan-Xia (黄燕霞), Li Hong (李宏)   

  1. College of Physics and Electronic Science, Hubei Normal University, Huangshi 435002, China
  • Received:2008-05-11 Revised:2008-05-29 Online:2008-11-20 Published:2008-11-20
  • Supported by:
    Project supported by the Key Higher Education Program of Hubei Province, China (Grant No Z20052201), Natural Science Foundation of Hubei Province, China (Grant No 2006ABA055) and Postgraduate Program of Hubei Normal University of China (Grant No 2007D20) .

摘要: By using the method of density-matrix renormalization-group to solve the different spin--spin correlation functions, the nearest-neighbouring entanglement (NNE) and the next-nearest-neighbouring entanglement (NNNE) of one-dimensional alternating Heisenberg XY spin chain are investigated in the presence of alternating the-nearest-neighbouring interaction of exchange couplings, external magnetic fields and the next-nearest neighbouring interaction. For a dimerised ferromagnetic spin chain, the NNNE appears only above a critical dimerized interaction, meanwhile, the dimerized interaction a effects a quantum phase transition point and improves the NNNE to a large extent. We also study the effect of ferromagnetic or antiferromagnetic next-nearest neighbouring (NNN) interaction on the dynamics of NNE and NNNE. The ferromagnetic NNN interaction increases and shrinks the NNE below and above a critical frustrated interaction respectively, while the antiferromagnetic NNN interaction always reduces the NNE. The antiferromagnetic NNN interaction results in a large value of NNNE compared with the case where the NNN interaction is ferromagnetic.

关键词: the entanglement, alternating XY spin chain, the next-nearest neighbouring interactions

Abstract: By using the method of density-matrix renormalization-group to solve the different spin--spin correlation functions, the nearest-neighbouring entanglement (NNE) and the next-nearest-neighbouring entanglement (NNNE) of one-dimensional alternating Heisenberg XY spin chain are investigated in the presence of alternating the-nearest-neighbouring interaction of exchange couplings, external magnetic fields and the next-nearest neighbouring interaction. For a dimerised ferromagnetic spin chain, the NNNE appears only above a critical dimerized interaction, meanwhile, the dimerized interaction a effects a quantum phase transition point and improves the NNNE to a large extent. We also study the effect of ferromagnetic or antiferromagnetic next-nearest neighbouring (NNN) interaction on the dynamics of NNE and NNNE. The ferromagnetic NNN interaction increases and shrinks the NNE below and above a critical frustrated interaction respectively, while the antiferromagnetic NNN interaction always reduces the NNE. The antiferromagnetic NNN interaction results in a large value of NNNE compared with the case where the NNN interaction is ferromagnetic.

Key words: the entanglement, alternating XY spin chain, the next-nearest neighbouring interactions

中图分类号:  (Quantized spin models, including quantum spin frustration)

  • 75.10.Jm
03.65.Ud (Entanglement and quantum nonlocality) 05.50.+q (Lattice theory and statistics) 75.30.Et (Exchange and superexchange interactions) 75.30.Kz (Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.)) 75.40.-s (Critical-point effects, specific heats, short-range order)