Localization-protected order in spin chains with non-Abelian discrete symmetries

Journal article

We study the nonequilibrium phase structure of the three-state random quantum Potts model in one dimension. This spin chain is characterized by a non-Abelian D 3 symmetry recently argued to be incompatible with the existence of a symmetry-preserving many-body localized (MBL) phase. Using exact diagonalization and a finite-size scaling analysis, we find that the model supports two distinct broken-symmetry MBL phases at strong disorder that either break the Z 3 clock symmetry or a Z 2 chiral symmetry. In a dual formulation, our results indicate the existence of a stable finite-temperature topological phase with MBL-protected parafermionic end zero modes. While we find a thermal symmetry-preserving regime for weak disorder, scaling analysis at strong disorder points to an infinite-randomness critical point between two distinct broken-symmetry MBL phases.

Authors: Friedman, A; Vasseur, R; Potter, A; Parameswaran, S

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Physical Society
• Journal: Physical Review B
• Volume: 98
• Issue: 6
• Article number: 064203
• Publication date: 2018-08-14
• Acceptance date: 2018-07-31
• DOI: 10.1103/PhysRevB.98.064203
• EISSN: 2469-9969
• ISSN: 2469-9950