Proximity-Induced Superconductivity at Non-Helical Topological Insulator Interfaces

Autor: David J. Alspaugh, Daniel E. Sheehy, Mahmoud M. Asmar, Ilya Vekhter
Rok vydání: 2018
Předmět:
DOI: 10.48550/arxiv.1807.04841
Popis: We study how non-helical spin textures at the boundary between a topological insulator (TI) and a superconductor (SC) affect the proximity-induced superconductivity of the TI interface state. We consider TIs coupled to both spin-singlet and spin-triplet SCs, and show that for the spin-triplet parent SCs the resulting order parameter induced onto the interface state sensitively depends on the symmetries which are broken at the TI-SC boundary. For chiral spin-triplet parent SCs, we find that nodal proximity-induced superconductivity emerges when there is broken twofold rotational symmetry which forces the spins of the non-helical topological states to tilt away from the interface plane. We furthermore show that the Andreev conductance of lateral heterostructures joining TI-vacuum and TI-SC interfaces yields experimental signatures of the reduced symmetries of the interface states.
Comment: 5 pages, 2 figures
Databáze: OpenAIRE