LMU Seminars

Interface driven superconductivity in topological insulator Fe-based superconductor heterostructures

by Dr Matthew Brahlek (Oak Ridge National Lab.)

Europe/Zurich
SZ-WBGB/019

SZ-WBGB/019

Description

Realizing exotic forms of superconductivity through epitaxially integrating high-transition-temperature (TC) superconductors with topological insulators can open new paths for quantum-based applications. In this talk, I will discuss how understanding molecular beam epitaxy growth has enable the creation interfaces with idealized spin-momentum locking and superconductivity as well as revealing hidden phenomena. Specifically, I will discuss how tailoring the synthesis of either member facilitates aligning the spin-momentum locked topological bandstructure of Bi2Te3 with the superconducting states of Fe(Te,Se). Furthermore, I will show how systematically reducing the Bi2Te3 can stabilize another topological phase, Bi4Te3, which when integrated with Fe(Te,Se) shifts the doping phase diagram and stabilizes superconductivity in the clean, low Se-doping regime. Changing the topological phase to Bi4Te3, moreover, is critical to stabilize superconductivity in monolayer Fe(Te,Se), where the strongest interactions of the topological and superconductivity states occurs. This novel route for epitaxial phase control at topological/superconducting interfaces provides new insight into the nature of unconventional superconductivity while being a new platform for identifying and utilizing new electronic phases.

Organised by

Zaher Salman

Zaher Salman