Regensburg 2025 – wissenschaftliches Programm

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

TT: Fachverband Tiefe Temperaturen

TT 48: Topology: Majorana Physics

TT 48.4: Vortrag

Donnerstag, 20. März 2025, 16:00–16:15, H32

Emerging Majorana bound states in superconducting Haldane nanoribbons — •Simone Traverso¹, Niccolò Traverso Ziani¹, Maura Sassetti¹, and Fernando Dominguez² — ¹Physics Department, University of Genoa and CNR-SPIN, 16146 Genoa, Italy — ²Faculty of Physics and Astrophysics and Würzburg-Dresden Cluster of Excellence ct.qmat, University of Würzburg, 97074 Würzburg, Germany

In the rapidly evolving field of quantum technologies, topological superconductors are promising platforms for topologically protected quantum computation. In this context, manipulating Majorana bound states (MBSs) would be a significant breakthrough.

We introduce a novel approach to designing MBSs, based on the geometric confinement of 2D nodal topological superconductors. We illustrate this mechanism in a superconducting extension of the Haldane model. In 2D, the model displays a nodal topological superconducting phase with chiral Majorana modes. However, by confining one of the dimensions the bulk bands gap out faster than the edge states, allowing for their hybridization and potentially resulting in Majorana zero modes. We assess their emergence by computing the topogical invariant for the quasi-1D setup and inspecting the energy spectrum of open flakes. Their topological nature is confirmed by the zero bias conductance in a normal-superconducting junction, precisely quantized to 2 e²/h in presence of an MBS. Our findings indicate quantum confinement as a crucial ingredient for developing quasi-1D topological superconducting phases starting from 2D nodal topological superconductors.

Keywords: Topological superconductivity; Honeycomb materials; Haldane model; Majorana; Quantum transport