Superconductivity protected by spin–valley locking in ion-gated MoS2
By Yu Saito, Yasuharu Nakamura, M. Bahramy, Y. Kohama, Jianting Ye, Y. Kasahara, Yuji Nakagawa, M. Onga, M. Tokunaga, T. Nojima and 2 more. Nature Physics, 2015
542 citations recorded by the source corpus.
The electric-field-induced superconducting properties of MoS2 are investigated by means of magneto-transport measurements, uncovering evidence of spin–momentum locking. Symmetry-breaking has been known to play a key role in non-centrosymmetric superconductors with strong spin–orbit interactions (SOIs; refs 1,2,3,4,5,6). The studies, however, have been so far mainly focused on a particular type of SOI, known as the Rashba SOI (ref. 7), whereby the electron spin is locked to its momentum at a right-angle, thereby leading to an in-plane helical spin texture. Here we discuss electric-field-induced superconductivity in molybdenum disulphide (MoS2), which exhibits a fundamentally different type of intrinsic SOI, manifested by an out-of-plane Zeeman-type spin polarization of energy valleys8,9,10. We find an upper critical field of approximately 52 T at 1.5 K, which indicates an enhancement of the Pauli limit by a factor of four as compared to that in centrosymmetric conventional superconductors. Using realistic tight-binding calculations, we reveal that this unusual behaviour is due to an inter-valley pairing that is symmetrically protected by Zeeman-type spin–valley locking against external magnetic fields. Our study sheds light on the interplay of inversion asymmetry with SOIs in confined geometries, and its role in superconductivity.
Subfields: Electronic, Optical and Magnetic Materials, Materials Chemistry
View Paper: https://www.semanticscholar.org/paper/4e9476092c83c05e6c45eedc59d77a0ddec5fcee
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
In Electronic, Optical and Magnetic Materials
In Materials Chemistry
Citations in the corpus
- Superconductivity in few-layer stanene (2017, background): “Of late, the realization of highly crystalline and atomically thin superconductors has triggered a flurry of discoveries including the Griffiths singularity behavior [3], a quantum metallic phase [4,5], as well as an extremely large critical magnetic field in the plane [6,7,8].”