Topological rf-SQUID with a frustrating pi-junction for probing the Majorana Bound State

TL;DR

This paper demonstrates that a pi-Josephson junction in a topologically non-trivial ring can host Majorana Bound States, which are robust and alter the ground state in measurable ways, offering a new probe for Majorana physics.

Contribution

It introduces a topological rf-SQUID with a pi-junction as a novel platform to detect Majorana Bound States in a realistic superconducting structure.

Findings

Majorana Bound States can exist in a pi-Josephson junction within a topological ring.

The presence of Majorana Bound States affects the ground state measurable in experiments.

The proposed structure is compatible with high-Tc superconductor tricrystal setups.

Abstract

Majorana Bound States are predicted to appear as boundary states of the Kitaev model. Here we show that a pi-Josephson Junction, inserted in a topologically non trivial model ring, sustains a Majorana Bound State, which is robust with respect to local and non local perturbations. The realistic structure could be based on a High Tc Superconductor tricrystal structure, similar to the one used to spot the d-wave order parameter. The presence of the Majorana Bound State changes the ground state of the topologically non trivial ring in a measurable way, with respect to that of a conventional one.