Quantum phase transition in the one-dimensional half-filled asymmetric Hubbard model

ORAL

Abstract

We study the quantum phase transition in the one-dimensional asymmetric Hubbard chain at half-filling in terms of spin stiffness by the exact diagonalization method. Since the phase transition is believed to be of Kosterlitz-Thouless type, no local order parameter can describe such a transition. We find instead that spin stiffness might be able to describe the quantum phase transition since the spin degree of freedom is gapless in the Hubbard region. while gapful in the Falicov-Kimball region.

*This work is supported by an Earmarked Grant for Research from the Research Grants Council of HKSAR, China (Project No. CUHK 400906).

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Authors

  • Yang Liu

    • Department of Physics, The Chinese University of Hong Kong

  • Wen-Ling Chan

    • Department of Physics, The Chinese University of Hong Kong

  • Shi-Jian Gu

    • The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
    • Department of Physics, The Chinese University of Hong Kong

  • Hai-Qing Lin

    • The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
    • The Chinese University of Hong Kong, Shatin, Hong Kong
    • Department of Physics and the Institute of Theoretical Physics, the Chinese University of Hong Kong
    • Department of Physics, The Chinese University of Hong Kong