Hybridization of Bound States in a TSC/TI/TSC Junction

It has been shown previously that a highly isolated and coherent qubit can be engineered by combining a topological superconducting Josephson junction with a microwave resonator into a device known as the Majorana-Transmon. Here we consider a related device where a topological insulator nanowire of type Bi2Se3 is proximitized to an s-wave Josephson junction. The resulting system is a topological superconducting junction with a topological insulator as the weak link. The Bi2Se3 nanowire is known for its significant surface states bandwidth and thus is an ideal candidate for a realization of the topologically protected Majorana edge states. We investigate the low energy Andreev bound states and the accompanying Majorana edge states residing in the junction. The hybridization between these states has a notable effect on the fermionic parity of the superconductors, and as a result on the dipole coupling between the junction and the cavity, which is evident in its electromagnetic signatures.