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arXiv · 0905.4895

Spontaneous Parity Violation in a Quantum Spin Chain

Stephan Rachel·Dirk Schuricht·Burkhard Scharfenberger·Ronny Thomale·Martin Greiter
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Abstract

We report on a spontaneous breakdown of parity in the ground state of a spin Hamiltonian involving nearest-neighbor interactions. This occurs for a one-dimensional model where spins transform under the gauge field representation of QCD, the eight-dimensional adjoint representation of SU(3). The ground state spontaneously violates parity and is two-fold degenerate. In addition, the model possesses a non-vanishing topological string order parameter which we explicate analytically.

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Stephan Rachel, Dirk Schuricht, Burkhard Scharfenberger, Ronny Thomale, Martin Greiter. 2009-05-29. Spontaneous Parity Violation in a Quantum Spin Chain. https://doi.org/10.1088/1742-6596/200/2/022049

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