Berlin 2024 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 67: Unconventional Superconductors
TT 67.9: Vortrag
Donnerstag, 21. März 2024, 12:00–12:15, H 3007
Quantum interference between quasi-2D Fermi surface sheets in UTe2 — •Theodore Weinberger1, Zheyu Wu1, David Graf2, Yurii Skourski3, Andrej Cabala4, Michal Vališka4, F. Malte Grosche1, and Alexander Eaton1 — 1Cavendish Laboratory, University of Cambridge, Cambridge, UK — 2NHMFL, Tallahassee, Florida, USA — 3HLD-EMFL, Dresden, DE — 4Department of Condensed Matter Physics, Charles University, Prague, CZ
Superconductivity in UTe2 exhibits extreme resilience to applied magnetic field, with critical fields exceeding 60 T. This, alongside the observation of distinct superconducting states in different regions of the phase diagram suggest unconventional, likely triplet pairing states. If a chiral pairing state were realised, this would mean that UTe2 could host topologically protected Majorana surface states. Quantum oscillation studies resolving the precise nature of the Fermi surface in UTe2, enabled by a new generation of high-quality crystals, provide valuable input for a full theoretical understanding of the topology of the pairing state. Here, we present and discuss high field contactless resistivity data, in which oscillations are observed with frequencies and effective masses that differ markedly from prior de Haas-van Alphen effect studies. These magnetoconductance oscillations can be understood as a quantum interference effect from quasiparticles tunnelling across quasi-2D Fermi surface sheets at high magnetic fields. A large variation in the apparent effective masses for the various interference paths yields valuable insight into the electronic bandstructure underpinning unconventional superconductivity in UTe2.
Keywords: Superconductivity; Uranium Based Superconductors; Magnetism; Quantum Oscillations