Anyon delocalization transitions out of a disordered FQAH insulator

arXiv:2506.02128 · cond-mat.str-el · Submitted 2025-06-02 · Read on arXiv

cond-mat.str-el

Submitted: 2025-06-02

Updated: 2025-06-11

Comments: 15 pages, 7 figures. v2: added refs and new discussion of anomalous vortex glass

Journal ref: Proc. Natl. Acad. Sci. U.S.A. 122 (51), e2520608122 (2025)

DOI: 10.1073/pnas.2520608122

License: http://creativecommons.org/licenses/by/4.0/

The gist: Motivated by the experimental discovery of the fractional quantum anomalous Hall (FQAH) effect, we develop a theory of doping-induced transitions out of the ν= 2/3 lattice Jain state in the presence

Terminology

Abstract

Motivated by the experimental discovery of the fractional quantum anomalous Hall (FQAH) effect, we develop a theory of doping-induced transitions out of the ν= 2/3 lattice Jain state in the presence of quenched disorder. We show that disorder strongly affects the evolution into the conducting phases described in our previous work. The delocalization of charge 2/3 anyons leads to a chiral topological superconductor through a direct second order transition for a smooth random potential with long-wavelength modulations. The longitudinal resistance has a universal peak at the associated quantum critical point. Close to the transition, we show that the superconducting ground state is an ``Anomalous Vortex Glass (AVG)'' stabilized in the absence of an external magnetic field. For short-wavelength disorder, this transition generically splits into three distinct ones with intermediate insulating topological phases. If instead, the charge 1/3 anyon delocalizes, then at low doping the result is a Reentrant Integer Quantum Hall state with ρ xy = h/e squared. At higher doping this undergoes a second transition to a Fermi liquid metal. We show that this framework provides a plausible explanation for the complex phase diagram recently observed in twisted MoTe 2 near ν= 2/3 and discuss future experiments that can test our theory in more detail.

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