Disorder-induced topological superconductivity in a spherical quantum-Hall--superconductor hybrid

Abstract

Quantum-Hall--Superconductor hybrids have been predicted to exhibit various types of topological order, providing possible platforms for intrinsically fault-tolerant quantum computing. In this paper, we develop a formulation to construct this hybrid system on a sphere, a useful geometry for identifying topologically ordered states due to its compact and contractible nature. As a preliminary step using this framework, we investigate disorder effects on the Rashba-coupled quantum Hall system combined with the type-II superconductor. By diagonalizing the BdG Hamiltonian projected into a Rashba-coupled Landau level, we demonstrate the emergence of a topological superconducting phase resulting from disorders and proximity-induced pairing. Distinctive gapless modes appear in the real-space entanglement spectrum, which is consistent with topological superconductivity.