Exploring parity transitions of Majorana bound states in S-TI-S lateral Josephson junctions*

It is predicted that S-TI-S lateral Josephson junctions, fabricated by depositing electrodes of a conventional superconductor (S) on the surface of a topological insulator (TI), exhibit Majorana bound states (MBS) at locations in the junction where the phase difference is an odd-multiple of π, i.e. at the cores of the Josephson vortices. There is evidence for this from the lifting of odd nodes in the critical current diffraction patterns and the observation of supercurrent features at magnetic field where the MBS enter the junction. In this talk, we report progress on experiments designed to probe the parity states of MBS pairs and the transitions between them via measurements of the critical current distribution and supercurrent fluctuations. These experiments give information about parity lifetimes and open the door to understand the factors that limit them.