Electronic Tunnelling in Superconductor/Quantum-Dot Josephson Junction Side-Coupled to Majorana Nanowire

We study the Josephson current (supercurrent) in a system consisting of two superconductors connected to a single-level quantum dot (QD), which is also side-coupled to a nanowire hosting Majorana bound states (MBSs). Our results show that the MBSs change both the peak height and position in the current-carrying density of states (CCDOS), and this determines the amplitude of the Josephson current due to the phase difference between the superconductors. By adjusting the energy level in the QD and MBSs-QD hybridization strengths, the magnetic flux penetrating through the closed circuit formed by the QD and the nanowire as well as the direct overlap between the MBSs, one can fully control the electron transport processes. The present results are useful in superconductor-based electrical devices and the newly developed area of superconducting coated conductors.

Automated summary

We investigate the Josephson current in a system with two superconductors connected to a quantum dot (QD) which is side-coupled to a nanowire hosting Majorana bound states (MBSs). Our findings demonstrate that the MBSs alter both the peak height and position in the current-carrying density of states (CCDOS), thereby determining the amplitude of the Josephson current. By adjusting the energy level in the QD and the hybridization strengths between MBSs and the QD, control over electron transport processes can be achieved. These results have implications for superconductor-based electronic devices and superconducting coated conductors.