Abstract The half-filled Hubbard chains with the Fibonacci and Harper modulating site potentials are studied in a self-consistent 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.
Received: 20 November 2007
Revised: 24 December 2007
Accepted manuscript online:
Fund: Project 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), and the Foundation for
Cite this article:
Zhu Xuan(朱璇) and Tong Pei-Qing(童培庆) Quantum phase transition and von Neumann entropy of quasiperiodic Hubbard chains 2008 Chin. Phys. B 17 1623
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