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arXiv · 2209.07824

Hybrid Symmetry Breaking in Classical Spin Models With Subsystem Symmetries

Giovanni Canossa·Lode Pollet·Ke Liu
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Abstract

We investigate two concrete cases of phase transitions breaking a subsystem symmetry. The models are two classical compass models featuring line-flip and plane-flip symmetries and correspond to special limits of a Heisenberg-Kitaev Hamiltonian on a cubic lattice. We show that these models experience a hybrid symmetry breaking by which the system display distinct symmetry broken patterns in different submanifolds. For instance, the system may look magnetic within a chain or plane but nematic-like when observing from one dimensionality higher. We fully characterize the symmetry-broken phases by a set of subdimensional order parameters and confirm numerically both cases undergo a non-standard first-order phase transition. Our results provide new insights into phase transitions involving subsystem symmetries and generalize the notion of conventional spontaneous symmetry breaking.

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Giovanni Canossa, Lode Pollet, Ke Liu. 2022-09-16. Hybrid Symmetry Breaking in Classical Spin Models With Subsystem Symmetries. https://doi.org/10.1103/physrevb.107.054431

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