Anyon superconductivity from topological criticality in a Hofstadter-Hubbard model

Area of Science:

• Condensed Matter Physics
• Quantum Materials
• Solid State Physics

Background:

• Electron pairing and superconductivity are typically mediated by attractive interactions.
• Moiré materials offer unique properties due to large lattice constants and tunable electronic structures.
• High magnetic fields and strong electron correlations are explored as alternative mechanisms for superconductivity.

Purpose of the Study:

• To investigate the emergence of electron pairing and superconductivity in a strongly correlated system under magnetic fields.
• To explore topological superconductivity in the Hofstadter-Hubbard model relevant to moiré materials.
• To realize a beyond-Bardeen-Cooper-Schrieffer mechanism for superconductivity.

Main Methods:

• Theoretical study of the triangular lattice Hofstadter-Hubbard model.
• Utilizing exact diagonalization and density matrix renormalization group (DMRG) methods.
• Examining the system at one-quarter flux quantum per plaquette and varying interaction strengths.

Main Results:

• Electronic pairing is observed on both sides of the integer quantum Hall to chiral spin liquid transition.
• Topological superconductivity emerges upon doping near this critical transition.
• A concrete model realization of anyon superconductivity is provided on the chiral spin liquid side.

Conclusions:

• The interplay of electron correlations and band topology can drive superconductivity.
• This work establishes a novel route to electron pairing in moiré-inspired models.
• The findings offer insights into realizing exotic quantum phenomena like anyon superconductivity.