Anyon superconductivity from topological criticality in a Hofstadter-Hubbard model

• 成果类型: Article
• 署名作者: Divic, Stefan; Crepel, Valentin; Soejima, Tomohiro; Song, Xue-Yang; Millis, Andrew J.; Zaletel, Michael P.; Vishwanath, Ashvin
• 署名单位: University of California System; University of California Berkeley; Simons Foundation; Flatiron Institute; Harvard University; Hong Kong University of Science & Technology; Columbia University; United States Department of Energy (DOE); Lawrence Berkeley National Laboratory
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-14986
• DOI: 10.1073/pnas.2426680122
• 发表日期: 2025-08-12
• 关键词: resonating-valence-bond; fractional chern insulators; ground-state; quantum; lattice; field; TRANSITION; Duality; dimensions; mechanism

摘要

We argue that the combination of strong repulsive interactions and high magnetic fields can generate electron pairing and superconductivity. Inspired by the large lattice constants of moir & eacute; materials, which make large flux per unit cell accessible at laboratory fields, we study the triangular lattice Hofstadter-Hubbard model at one-quarter flux quantum per plaquette, where previous literature has argued that a chiral spin liquid separates a weak-coupling integer quantum Hall phase and a strong-coupling topologically trivial antiferromagnetic insulator at a density of one electron per site. We argue that topological superconductivity emerges upon doping in the vicinity of the integer quantum Hall to chiral spin liquid transition. We employ exact diagonalization and density matrix renormalization group methods to examine this theoretical scenario and find that electronic pairing indeed occurs on both sides of criticality over a remarkably broad range of interaction strengths. On the chiral spin liquid side, our results provide a concrete model realization of the long-hypothesized mechanism of anyon superconductivity. Our study thus establishes a beyond-Bardeen-Cooper-Schrieffer route to electron pairing in a well-controlled limit, relying crucially on the interplay between electron correlations and band topology.