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Spontaneous Symmetry Breakings in $Z_2$ Gauge Theories for Doped Quantum Dimer and Eight-Vertex Models

Ikuo Ichinose·Daisuke Yoshioka
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Abstract

Behavior of doped fermions in $Z_2$ gauge theories for the quantum dimer and eight-vertex models is studied. Fermions carry charge and spin degrees of freedom. In the confinement phase of the $Z_2$ gauge theories, these internal symmetries are spontaneously broken and a superconducting or Neél state appears. On the other hand in the deconfinement-topologically-ordered state, all symmetries are respected. From the view point of the quantum dimer and eight-vertex models, this result indicates interplay of the phase structure of the doped fermions and background configuration of the dimer or the eight-vertex groundstate. At the quantum phase transitions in these systems, structure of the doped-fermions groundstate and also that of the background dimer or eight-vertex groundstate both change. Translational symmetry breaking induces a superconducting or antiferromagnetic state of the doped fermions.

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Ikuo Ichinose, Daisuke Yoshioka. 2004-11-11. Spontaneous Symmetry Breakings in $Z_2$ Gauge Theories for Doped Quantum Dimer and Eight-Vertex Models. https://doi.org/10.1016/j.aop.2004.12.008

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