Fragility of Symmetry Protected Topological Order on a Hubbard Ladder

Sanjay Moudgalya; Frank Pollmann

doi:10.1103/physrevb.91.155128

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arXiv · 1412.6814

Fragility of Symmetry Protected Topological Order on a Hubbard Ladder

Sanjay Moudgalya·Frank Pollmann

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Abstract

Anfuso and Rosch [Phys. Rev. B 75, 144420 (2007)] showed that the "topological" Haldane phase in a fermionic spin-1/2 ladder can be continuously deformed into a "trivial" phase without explicitly breaking symmetries when local charge fluctuations are taken into account. Within the framework of symmetry protected topological phases, we revisit the model and demonstrate how the Haldane phase can be adiabatically connected to a trivial phase due to charge fluctuations. Furthermore, we show that the Haldane phase remains stable as long as the system is symmetric under particular reflection symmetries.

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Sanjay Moudgalya, Frank Pollmann. 2014-12-21. Fragility of Symmetry Protected Topological Order on a Hubbard Ladder. https://doi.org/10.1103/physrevb.91.155128

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