Quantum Resistor-Capacitor Circuit with Majorana Fermion Modes in Chiral Topological Superconductor

Abstract

We investigate the mesoscopic resistor-capacitor circuit consisting of a quantum dot coupled to spatially separated Majorana fermion modes in a chiral topological superconductor. We find substantially enhanced relaxation resistance due to the nature of Majorana fermions, which are their own anti-particles and composed of particle and hole excitations in the same abundance. Further, if only a single Majorana mode is involved, the zero-frequency relaxation resistance is completely suppressed due to a destructive interference. As a result, the Majorana mode opens an exotic dissipative channel on a superconductor which is typically regarded as dissipationless due to its finite superconducting gap.

To appear in Phys. Rev. Lett.; Supplemental Material available at http://iff.korea.ac.kr/Opus/ChoiMS14c-Suppl.pdf; References and Suppl. Mat. updated