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arXiv · 2102.06383

Symmetry protected topological edge modes and emergent partial time reversal symmetry breaking in open quantum many-body systems

Zijian Wang·Qiaoyi Li·Wei Li·Zi Cai
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Abstract

Symmetry-protected topological edge modes are one of the most remarkable phenomena in topological physics. Here, we formulate and quantitatively examine the effect of a quantum bath on these topological edge modes. Using the density matrix renormalization group method, we study the ground state of a composite system of spin-1 quantum chain, where the system and the bath degrees of freedom are treated on the same footing. We focus on the dependence of these edge modes on the global/partial symmetries of system-bath coupling and on the features of the quantum bath. It is shown that the time-reversal symmetry(TRS) plays a special role for an open quantum system, where an emergent partial TRS breaking will result in a TRS-protected topological mode diffusing from the system edge into the bath, thus make it useless for quantum computation.

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Zijian Wang, Qiaoyi Li, Wei Li, Zi Cai. 2021-02-12. Symmetry protected topological edge modes and emergent partial time reversal symmetry breaking in open quantum many-body systems. https://doi.org/10.1103/physrevlett.126.237201

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