Two-gap s± -wave superconductivity at an oxide interface
Artikel i vetenskaplig tidskrift, 2022
After half a century of debate, superconductivity in doped SrTiO3 has come to the fore again with the discovery of interfacial superconductivity in the LaAlO3 /SrTiO3 heterostructures. While these interfaces share the interesting properties of bulk SrTiO3, quantum confinement generates a complex band structure involving bands with different orbital symmetries whose occupancy is tunable by electrostating doping. Multigap superconductivity has been predicted to emerge in LaAlO3 /SrTiO3 at large doping, with a Bose-Einstein condensation character at the Lifshtiz transition. In this article, we report on the measurement of the upper critical magnetic field Hc2 of superconducting (110)-oriented LaAlO3 /SrTiO3 heterostructures and evidence a two-gap superconducting regime at high doping. Our results are quantitatively explained by a theoretical model based on the formation of an unconventional s±-wave superconducting state with a repulsive coupling between the two condensates.
Författare
Gyanendra Singh
Institut de Ciència de Materials de Barcelona (ICMAB-CSIC)
Université de recherche Paris Sciences et Lettres
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
G. Venditti
Sapienza, Università di Roma
Istituto Dei Sistemi Complessi, Rome
G. Saiz
Université de recherche Paris Sciences et Lettres
G. Herranz
Institut de Ciència de Materials de Barcelona (ICMAB-CSIC)
F. Sánchez
Institut de Ciència de Materials de Barcelona (ICMAB-CSIC)
A. Jouan
Université de recherche Paris Sciences et Lettres
C. Feuillet-Palma
Université de recherche Paris Sciences et Lettres
J. Lesueur
Université de recherche Paris Sciences et Lettres
M. Grilli
Sapienza, Università di Roma
Istituto Dei Sistemi Complessi, Rome
S. Caprara
Istituto Dei Sistemi Complessi, Rome
Sapienza, Università di Roma
N. Bergeal
Université de recherche Paris Sciences et Lettres
Physical Review B
24699950 (ISSN) 24699969 (eISSN)
Vol. 105 6 064512Ämneskategorier
Annan fysik
Teoretisk kemi
Den kondenserade materiens fysik
DOI
10.1103/PhysRevB.105.064512