Quantum criticality in the 2d quasiperiodic Potts model

TL;DR

This paper investigates quantum phase transitions in a 2D quasiperiodic Potts model, revealing a universal critical behavior governed by an infinite-quasiperiodicity fixed point with a correlation length exponent of 1.

Contribution

It introduces a controlled real-space renormalization group analysis showing that the critical behavior is largely independent of the number of states q in the quasiperiodic Potts model.

Findings

Critical behavior is governed by an infinite-quasiperiodicity fixed point.

Correlation length exponent is ν=1, saturating a modified Harris-Luck criterion.

Critical properties are largely independent of q.

Abstract

Quantum critical points in quasiperiodic magnets can realize new universality classes, with critical properties distinct from those of clean or disordered systems. Here, we study quantum phase transitions separating ferromagnetic and paramagnetic phases in the quasiperiodic $q$-state Potts model in $2+1d$. Using a controlled real-space renormalization group approach, we find that the critical behavior is largely independent of $q$, and is controlled by an infinite-quasiperiodicity fixed point. The correlation length exponent is found to be $\nu=1$, saturating a modified version of the Harris-Luck criterion.