Quantum phase transition and von Neumann entropy of quasiperiodic Hubbard chains  

作　　者：朱璇 童培庆 

机构地区：[1]Department of Physics, Nanjing Normal University

出　　处：《Chinese Physics B》2008年第5期1623-1628,共6页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos 90203009, 10175035 and 10674072);the Specialized Research Fund for the Doctoral Programme (SRFDP) of Higher Education of China (Grant No 20060319007);the Foundation for outstanding Young Teacher of Ministry of Education of China

摘　　要：The half-filled Hubbard chains with the Fibonacci and Harper modulating site potentials are studied in a selfconsistent mean-field approximation. A new order parameter is introduced to describe a charge density order. We also calculate the von Neumann entropy of the ground state. The results show that the von Neumann entropy can identify a CDW/SDW （charge density wave/spin density wave） transition for quasiperiodic models.The half-filled Hubbard chains with the Fibonacci and Harper modulating site potentials are studied in a selfconsistent mean-field approximation. A new order parameter is introduced to describe a charge density order. We also calculate the von Neumann entropy of the ground state. The results show that the von Neumann entropy can identify a CDW/SDW （charge density wave/spin density wave） transition for quasiperiodic models.

关 键 词：von Neumann entropy QUASIPERIODICITY Hubbard model spin-density waves 

分 类 号：O413.1[理学—理论物理]