Gate-tunable pairing channels in superconducting non-centrosymmetric oxides nanowires
Journal article, 2022
Two-dimensional SrTiO3-based interfaces stand out among non-centrosymmetric superconductors due to their intricate interplay of gate-tunable Rashba spin-orbit coupling and multi-orbital electronic occupations, whose combination theoretically prefigures various forms of non-standard superconductivity. By employing superconducting transport measurements in nano-devices we present strong experimental indications of unconventional superconductivity in the LaAlO3/SrTiO3 interface. The central observations are the substantial anomalous enhancement of the critical current by small magnetic fields applied perpendicularly to the plane of electron motion, and the asymmetric response with respect to the magnetic field direction. These features cannot be accommodated within a scenario of canonical spin-singlet superconductivity. We demonstrate that the experimental observations can be described by a theoretical model based on the coexistence of Josephson channels with intrinsic phase shifts. Our results exclude a time-reversal symmetry breaking scenario and suggest the presence of anomalous pairing components that are compatible with inversion symmetry breaking and multi-orbital physics.
Author
Gyanendra Singh
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Claudio Guarcello
Complesso Univ Monte S Angelo
University of Salerno
Edouard Lesne
Delft University of Technology
Dag Winkler
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Tord Claeson
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Thilo Bauch
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Floriana Lombardi
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Andrea D. Caviglia
Delft University of Technology
Roberta Citro
Complesso Univ Monte S Angelo
University of Salerno
Mario Cuoco
University of Salerno
Alexei Kalaboukhov
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
NPJ QUANTUM MATERIALS
2397-4648 (eISSN)
Vol. 7 1 2Multifunktionella gränsytor i komplexa metalloxider för styrbar elektronik
Swedish Research Council (VR) (2016-05256), 2017-01-01 -- 2020-12-31.
Subject Categories
Other Physics Topics
Fusion, Plasma and Space Physics
Condensed Matter Physics
DOI
10.1038/s41535-021-00406-6