Probing the magnetoelectric effect in noncentrosymmetric superconductors by equal-spin Andreev tunneling. (19th December 2018)

• Record Type: Journal Article
• Authors: Tkachov, G
• Is Part Of: Journal of physics. Volume 31:Number 5(2019)
• Publication Date: 2018-12-19
• Subjects: Andreev reflection -- spin–orbit coupling -- noncentrosymmetric superconductors -- spin-triplet pairing -- Green's functions; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/aaf337
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: In noncentrosymmetric superconductors (NCSs), the conversion of a charge current into spin magnetization—the so called magnetoelectric effect—is the direct indicator of the unconventional, mixed-parity order parameter. This paper proposes a scheme to detect the magnetoelectric effect by anomalous, equal-spin Andreev tunneling in NCS/ferromagnet contacts. The proposal relies on the ability to generate spin-polarized triplet pairing by passing an electric current through an NCS. Such an induced triplet pairing bears a similarity to the paradigmatic nonunitary pairing in triplet superfluids with a complex vector order parameter . The qualitative difference is that the induced nonunitary state can be realised in NCSs with a purely real by breaking the time-reversal symmetry in current-biased setups. This offers a possibility to access the unconventional superconductivity in NCSs through electrical transport measurements.