Scaling of emergent symmetry at a first-order transition in the simplest classical model
Abstract
Emergent symmetry has attracted attention due to its possible connections with deconfined quantum criticality, where the phase boundary between a dimerized and a Neel phase is generically continuous, contrary to the standard Ginzburgb-Landau picture where a first-order phase transition is predicted. While emergent symmetries of multicritical points have been studied in various ways, less is known about how the emergent symmetry remains at the first-order transition line starting from such multicritical points. In this study, we analyze a simple model with two competing orders, by extensive Monte-Carlo simulation. The model has three phases (one paramagnetic and two Z2 symmetry-breaking phases) when varying the temperature and a parameter in the Hamiltonian. We observe that the bicritical point where the three phases meet has emergent O(2) symmetry, as predicted by field-theory. Furthermore, we find that the first-order transition line separating two ordered phases has a remainder of the emergent symmetry up to a certain length scale. We quantitatively discuss how this length scale diverges.
This work was supported by NSF DMR-1710170 and Simons Foundation.- Publication:
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APS March Meeting Abstracts
- Pub Date:
- 2019
- Bibcode:
- 2019APS..MARP18011T