Exotic circuit elements from zero-modes in hybrid superconductor-quantum Hall systems

Abstract

The fractional quantum Hall effect and superconductivity, remarkable phenomena in their own right, can harbour even more exotic physics at their interface. In particular, coupling quantum Hall edges with a superconductor can create emergent excitations known as non-Abelian anyons that trap widely coveted Majorana fermion zero-modes and generalizations thereof. We uncover non-local transport signatures of these zero-modes that not only provide striking experimental signatures of the anyons, but moreover allow one to construct novel circuit elements, including superconducting current and voltage mirrors, fractional charge transistors and flux-based capacitors. Underlying this unusual transport is a phenomenon that we term ‘perfect Andreev conversion’—whereby quasiparticles propagating chirally at the edge reverse their electric charge as a result of hybridization with the zero-modes. Our findings suggest numerous experimental directions in the study of quantum-Hall–superconductor systems hybrids and highlight a fundamentally new application of non-Abelian anyons.