Josephson dc Current through T-Shaped Double-Quantum-Dots Hybridized to Majorana Nanowires

Abstract

We study quantum interference effects on Josephson current in T-shaped double quantum dots (TDQDs) with one of them (the central dot) is sandwiched between the left and right topological superconductor nanowires hosting Majorana bound states (MBSs). We find that the current’s magnitude is suppressed by the inter-dot coupling that induces the quantum interference effect, with unchanged jump in the current at particular phase difference between the two nanowires from which the Josephson effect arises. The current remains as a sinusoidal function with respective to the phase difference in the presence of quantum interference effect, but with significant reduction. The central broad peak in the curve of the Josephson current versus the QDs’ levels are split in different ways depending on the configurations of the latter. We also find that the impacts of the non-z-axial direction magnetic field, bending angle between the two nanowires and the direct hybridization amplitude between the MBSs on the current all depend on the arrangement of the QDs’ energy levels.