171103 Quantum Resistor-Capacitor Circuit with Majorana Edge States

“Quantum Resistor-Capacitor Circuit with Majorana Edge States”

Dr. MinChul Lee
Department of Applied Physics, Kyung Hee University

Nov. 3 (Fri.), 02:30 PM
E6-2. 1st fl. #1323

Abstract:
In this talk we present the recent studies on the charge relaxation in the mesoscopic resistor-capacitor circuit consisting of a quantum dot coupled to Majorana fermion modes. Here we consider two Majorana edge modes: (1) the edge modes in a chiral topological superconductor and (2) the localized Majorana bound state formed at the end of a superconducting wire. In both cases, we report a complete suppression of the low-frequency charge relaxation due to a Majorana-oriented destructive interference if some conditions are met. On the other hand, by tuning the dot level or the overlap between Majorana bound states, the relaxation resistance can be substantially enhanced, which is also due to the nature of Majorana fermions, which are their own antiparticles and are composed of particle and hole excitations in the same abundance. Finally, we discuss the possibility that the quantum capacitance in Majorana systems is not necessarily proportional to the density of states.