Regensburg 2025 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

TT: Fachverband Tiefe Temperaturen

TT 51: Topological Superconductors

TT 51.5: Vortrag

Donnerstag, 20. März 2025, 17:45–18:00, H32

Topological Classification of Chiral Symmetric One Dimensional Interfaces — •Harry MullineauxSanders and Bernd Braunecker — University of St. Andrews, St. Andrews, United Kingdom

Low dimensional topological phases can be engineered by placing a scattering interface into a higher dimensional bulk where the in-gap bands of quasi low dimensional interface modes can be tuned to a topologically non-trivial phase. However the classification of such modes cannot be done through low-dimensional conventional methods due to the dimensional mismatch and local nature of the topological bands. We demonstrate that there exists a simple and efficient classification method through the local Green's function at the interface, that sidesteps numerically heavy real space computations. We show that the Green's function maintains the protecting symmetries of the Hamiltonian and produces the correct phase diagram, together with a formula disentangling the contributions to the topological invariant from the substrate and the interface. For illustration we apply our method to a model of a spiral magnetic interface in an s-wave superconductor. Furthermore we compare with an alternative classification scheme derived from the spatially reduced ground state projector and show that it can produce an erroneous topological classification due to gap closures driven by the strong entanglement between the internal and spatial degrees of freedom which are naturally contained in the local Green's function. [arXiv:2407.01223]

Keywords: Topological Superconductivity; Magnetic Textures; Interfaces