Symmetry-protected topological phases beyond groups: The q-deformed Affleck-Kennedy-Lieb-Tasaki model

Article

关键词: QUANTUM SPIN CHAINS;    Q-DEFORMATIONS;    STATES;    BREAKING;   

DOI  :  10.1103/PhysRevB.102.081120

来源: SCIE

【 摘 要 】

We argue that the q-deformed spin-1 Affleck-Kennedy-Lieb-Tasaki (AKLT) Hamiltonian should be regarded as a representative of a symmetry-protected topological phase. Even though it fails to exhibit any of the standard symmetries known to protect the Haldane phase, it still displays all characteristics of this phase: fractionalized spin-1/2 boundary spins, nontrivial string order, and-when using an appropriate definition-a twofold degeneracy in the entanglement spectrum. We trace these properties back to the existence of an SOq(3) quantum group symmetry and speculate about potential links to discrete duality symmetries. We expect our findings and methods to be relevant for the identification, characterization, and classification of other symmetry-protected topological phases with nonstandard symmetries.

【 授权许可】

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