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arXiv · 1003.0216

Spontaneous breaking of four-fold rotational symmetry in two-dimensional electron systems as a topological phase transition

M. V. Zverev·J. W. Clark·Z. Nussinov·V. A. Khodel
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Abstract

Motivated by recent observations of $C_4$ symmetry breaking in strongly correlated two-dimensional electron systems on a square lattice, we analyze this phenomenon within an extended Fermi liquid approach. It is found that the symmetry violation is triggered by a continuous topological phase transition associated with exchange of antiferromagnetic fluctuations. In contrast to predictions of mean-field theory, the structure of a part of the single-particle spectrum violating $C_4$ symmetry is found to be highly anisotropic, with a peak located in the vicinity of saddle points.

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M. V. Zverev, J. W. Clark, Z. Nussinov, V. A. Khodel. 2010-08-24. Spontaneous breaking of four-fold rotational symmetry in two-dimensional electron systems as a topological phase transition. https://doi.org/10.1103/physrevb.82.125111

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