Majorana modes in a triple-terminal Josephson junction with embedded parallel-coupled double quantum dots

TL;DR

This paper explores the Josephson effect in a triple-terminal junction with double quantum dots, revealing robust 4π-period oscillations and proposing a feasible way to realize Majorana modes in a nonmagnetic system.

Contribution

It introduces a novel setup for observing Majorana modes using a triple-terminal Josephson junction with embedded double quantum dots, independent of fermion parity and Coulomb interactions.

Findings

Supercurrent oscillates with 4π period under phase adjustments.

Majorana modes are analytically defined via superpositions of electron and hole operators.

The results are robust against various system parameters.

Abstract

We investigate the Josephson effect in one triple-terminal junction with embedded parallel-coupled double quantum dots. It is found that the inter-superconductor supercurrent has opportunities to oscillate in $4\pi$ period, with the adjustment of the phase differences among the superconductors. What is notable is that such a result is robust and independent of fermion parities, intradot Coulomb strength, and the dot-superconductor coupling manner. By introducing the concept of spinful many-particle Majorana modes, we present the analytical definition of the Majorana operator via superposing electron and hole operators. It can be believed that this work provide a simple but feasible proposal for the realization of Majorana modes in a nonmagnetic system.