Abstract

We present a topological mechanism for superconductivity emerging from Chern-2 insulators. While, naively, time-reversal symmetry breaking is expected to prevent superconductivity, an explicit model calculation for a generalized attractive-U Haldane-Hubbard model demonstrates that superconductivity is stabilized near the quantum anomalous Hall state, but not near a trivial, time-reversal symmetric band insulator. Using a fractionalized field theory with fermionic chargeons, bosonic colorons, and an emergent U(1) gauge field, together with slave-rotor mean-field theory, random phase approximation, an effective spin model, and Gutzwiller-projected wavefunctions, the work characterizes coherence length, stiffness, phase diagram, and the effects of doping, temperature, and magnetic field. The authors argue that these results are relevant to superconductivity emerging in spin- and valley-polarized rhombohedral graphene multilayers near quantum anomalous Hall insulators.

Abstract

We present a topological mechanism for superconductivity emerging from Chern-2 insulators. While, naively, time-reversal symmetry breaking is expected to prevent superconductivity, an explicit model calculation for a generalized attractive-U Haldane-Hubbard model demonstrates that superconductivity is stabilized near the quantum anomalous Hall state, but not near a trivial, time-reversal symmetric band insulator. Using a fractionalized field theory with fermionic chargeons, bosonic colorons, and an emergent U(1) gauge field, together with slave-rotor mean-field theory, random phase approximation, an effective spin model, and Gutzwiller-projected wavefunctions, the work characterizes coherence length, stiffness, phase diagram, and the effects of doping, temperature, and magnetic field. The authors argue that these results are relevant to superconductivity emerging in spin- and valley-polarized rhombohedral graphene multilayers near quantum anomalous Hall insulators.

Abstract

We present a topological mechanism for superconductivity emerging from Chern-2 insulators. While, naively, time-reversal symmetry breaking is expected to prevent superconductivity, an explicit model calculation for a generalized attractive-U Haldane-Hubbard model demonstrates that superconductivity is stabilized near the quantum anomalous Hall state, but not near a trivial, time-reversal symmetric band insulator. Using a fractionalized field theory with fermionic chargeons, bosonic colorons, and an emergent U(1) gauge field, together with slave-rotor mean-field theory, random phase approximation, an effective spin model, and Gutzwiller-projected wavefunctions, the work characterizes coherence length, stiffness, phase diagram, and the effects of doping, temperature, and magnetic field. The authors argue that these results are relevant to superconductivity emerging in spin- and valley-polarized rhombohedral graphene multilayers near quantum anomalous Hall insulators.

Abstract

We present a topological mechanism for superconductivity emerging from Chern-2 insulators. While, naively, time-reversal symmetry breaking is expected to prevent superconductivity, an explicit model calculation for a generalized attractive-U Haldane-Hubbard model demonstrates that superconductivity is stabilized near the quantum anomalous Hall state, but not near a trivial, time-reversal symmetric band insulator. Using a fractionalized field theory with fermionic chargeons, bosonic colorons, and an emergent U(1) gauge field, together with slave-rotor mean-field theory, random phase approximation, an effective spin model, and Gutzwiller-projected wavefunctions, the work characterizes coherence length, stiffness, phase diagram, and the effects of doping, temperature, and magnetic field. The authors argue that these results are relevant to superconductivity emerging in spin- and valley-polarized rhombohedral graphene multilayers near quantum anomalous Hall insulators.