Quantum transport through a quantum dot coupled to a pair of superconducting topological nanowires

Abstract

Abstract In this study, we analyze quantum transport using a quantum dot coupled to four Majorana bound states confined to the ends of two superconducting topological nanowires. Particularly, we investigate how quantum transport affects the magnetic flux phase of the second nanowire and electron-phonon interaction. When the Majorana bound states are hybridized, the periodicity of zero-temperature linear conductance shifts from 2 π to 4 π . This takes place as the magnetic flux phase of the second nanowire changes from states with zero-energy modes to states without it. However, during the fixed magnetic flux phase, the zero-energy modes appear toward the end of the second nanowaire. Indeed, we observe that the periodicity goes from 4 π to 2 π when we change the Majorana bound states from unhybridized to hybridized states. Linear conductance is measured independently of electron-phonon interactions and quantum dot energy. Furthermore, we show that the differential conductance periodicity changes from 2 π when the Majorana bound states are nonoverlapping. It achieves 4 π periodicity if the Majorana bound states overlap with regard to a magnetic flux phase in a state without zero-energy modes. Nevertheless, a state with zero-energy modes of the magnetic flux phase remains fixed at 4 π . Finally, we conclude that our results illuminate the expected behavior of topological quantum computational platforms.