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arXiv · 1512.05229

Chiral Haldane phases of SU(N) quantum spin chains in the adjoint representation

Abhishek Roy·Thomas Quella
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Abstract

Gapped quantum spin chains with symmetry PSU(N)=SU(N)/Z(N) are known to possess N distinct symmetry protected topological phases. Besides the trivial phase, there are N-1 Haldane phases which are distinguished by the occurrence of massless boundary spins. Motivated by the potential realization in alkaline-earth atomic Fermi gases, we explicitly construct previously unknown Hamiltonians for two classes of chiral AKLT states and we discuss their physical properties. We also point out a deep connection between symmetry protection in gapped and gapless 1D quantum spin systems and its implications for a potential multicritical nature of topological phase transitions.

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Abhishek Roy, Thomas Quella. 2015-12-16. Chiral Haldane phases of SU(N) quantum spin chains in the adjoint representation. https://doi.org/10.1103/physrevb.97.155148

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