Signatures of broken parity and time-reversal symmetry in generalized string-net models

Article

关键词: TOPOLOGICAL ORDERS;    FUSION CATEGORIES;    EXCITATIONS;    ANYONS;    STATES;   

DOI  :  10.1103/PhysRevB.94.115139

来源: SCIE

【 摘 要 】

We study indicators of broken time-reversal and parity symmetries in gapped topological phases of matter. We focus on phases realized by Levin-Wen string-net models and generalize the string-net model to describe phases which break parity and time-reversal symmetries. We do this by introducing an extra degree of freedom into the string-net graphical calculus, which takes the form of a branch cut located at each vertex of the underlying string-net lattice. We also work with string-net graphs defined on arbitrary (nontrivalent) graphs, which reveals otherwise hidden information about certain configurations of anyons in the string-net graph. Most significantly, we show that objects known as higher Frobenius-Schur indicators can provide several efficient ways to detect whether a given topological phase breaks parity or time-reversal symmetry.

【 授权许可】

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