Pressemitteilung zu Neuartiger Oberflächensupraleitung in topologischem Material
Pressemitteilung
Eine ausführlicherere Mitteilung enthält die Dekanatsseite der Fachgruppe Physik:
Kurze Erläuterung zum Artikel von Professor Christian Hemker-Heß sowie das Abstract des Artikels
„Unsere Resultate eröffnen beeindruckende Perspektiven für die Grundlagenforschung und zukünftige technologische Anwendungen, etwa im Bereich des Quanten-Computings“, sagt Prof. Dr. Christian Hemker-Heß vom Wuppertaler Lehrstuhl für Kondensierte Materie – Experimentelle Festkörperphysik.
Abstract
Topological superconductivity is a promising concept for generating fault-tolerant qubits. Early experimental studies looked at hybrid systems and doped intrinsic topological or superconducting materials at very low temperatures. However, higher critical temperatures are indispensable for technological exploitation. Recent angle-resolved photoemission spectroscopy results have revealed that superconductivity in the type-I Weyl semimetal—trigonal PtBi2 (t-PtBi2)—is located at the Fermi-arc surface states, which renders the material a potential candidate for intrinsic topological superconductivity. Here we show, using scanning tunnelling microscopy and spectroscopy, that t-PtBi2 presents surface superconductivity at elevated temperatures (5 K). The gap magnitude is elusive: it is spatially inhomogeneous and spans from 0 to 20 meV. In particular, the large gap value and the shape of the quasiparticle excitation spectrum resemble the phenomenology of high-Tc superconductors. To our knowledge, this is the largest superconducting gap so far measured in a topological material. Moreover, we show that the superconducting state at 5 K persists in magnetic fields up to 12 T.
