Inverse proximity effects of a topological insulator on a superconductor in one-dimensional heterostructures

Superconductor–topological insulator heterostructures are a leading route to engineered topological superconductivity. Most work focuses on the forward proximity effect — how superconducting order leaks into the topological insulator — but the back-action, how the topological insulator modifies the superconductor itself, is far less understood.

This work examines the inverse proximity effect in the quasi-one-dimensional limit, asking how topological bound states at the interface inhibit superconducting order in the parent superconductor. The analysis uses quasi-classical Green’s function methods to characterize the transition temperature and critical fields, and traces how surface states determine superconducting properties in these heterostructures.

Work with Prof. Hridis K. Pal, IIT Bombay, extending my Master’s thesis on topological insulator–superconductor junctions.