A1 Journal article (refereed)
Proximity effect in superconducting heterostructures with strong spin-orbit coupling and spin splitting (2019)
Lu, Y., & Heikkilä, T. T. (2019). Proximity effect in superconducting heterostructures with strong spin-orbit coupling and spin splitting. Physical Review B, 100(10), Article 104514. https://doi.org/10.1103/PhysRevB.100.104514
JYU authors or editors
Publication details
All authors or editors: Lu, Yao; Heikkilä, Tero T.
Journal or series: Physical Review B
ISSN: 2469-9950
eISSN: 2469-9969
Publication year: 2019
Volume: 100
Issue number: 10
Article number: 104514
Publisher: American Physical Society
Publication country: United States
Publication language: English
DOI: https://doi.org/10.1103/PhysRevB.100.104514
Publication open access: Not open
Publication channel open access:
Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/65943
Publication is parallel published: https://arxiv.org/abs/1905.11135
Abstract
It has been shown that singlet Cooper pairs can be converted into triplet ones and diffuse into a ferromagnet over a long distance in a phenomenon known as the long-range proximity effect (LRPE). This happens in materials with inhomogeneous magnetism or spin-orbit coupling (SOC). Most of the previous studies focus on the cases with small SOC and exchange field. However, the physics was not clear when SOC and exchange field strength are both much greater than the disorder strength. In this work, we consider a two-dimensional system with a large Rashba-type SOC and exchange field in the case where only one band is partially occupied. We develop a generalized quasiclassical theory by projecting the Green function onto the partially occupied band (POB). We find that when the SOC energy scale is comparable with the exchange field, there is no LRPE. The reason is that the nonmagnetic impurities together with the large SOC and exchange field can effectively generate spin-flip scattering, which suppresses the proximity effect. We also show that when increasing either SOC or exchange field, the decay length of superconducting correlations can be significantly increased due to an approximately restored time reversal symmetry or spin rotation symmetry around the z (out-of-plane) axis.
Keywords: superconductivity; superconductors; magnetism
Contributing organizations
Related projects
- Hybrid nanoelectronic systems in and out of the quantum limit
- Heikkilä, Tero
- Research Council of Finland
Ministry reporting: Yes
Reporting Year: 2019
JUFO rating: 2