Long-lived non-equilibrium superconductivity in a non-centrosymmetric Rashba semiconductor

V. Narayan; P. C. Verpoort; J. R. A. Dann; D. Backes; C. J. B. Ford; M. Lanius; A. R. Jalil; P. Schüffelgen; G. Mussler; G. J. Conduit; D. Grützmacher

doi:10.1103/physrevb.100.024504

arXiv · 1902.04675

Long-lived non-equilibrium superconductivity in a non-centrosymmetric Rashba semiconductor

V. Narayan·P. C. Verpoort·J. R. A. Dann·D. Backes·C. J. B. Ford·M. Lanius·A. R. Jalil·P. Schüffelgen·G. Mussler·G. J. Conduit·D. Grützmacher

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Abstract

We report non-equilibrium magnetodynamics in the Rashba-superconductor GeTe, which lacks inversion symmetry in the bulk. We find that at low temperature the system exhibits a non-equilibrium state, which decays on time scales that exceed conventional electronic scattering times by many orders of magnitude. This reveals a non-equilibrium magnetoresponse that is asymmetric under magnetic field reversal and, strikingly, induces a non-equilibrium superconducting state distinct from the equilibrium one. We develop a model of a Rashba system where non-equilibrium configurations relax on a finite timescale which captures the qualitative features of the data. We also obtain evidence for the slow dynamics in another non-superconducting Rashba system. Our work provides novel insights into the dynamics of non-centrosymmetric superconductors and Rashba systems in general.

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V. Narayan, P. C. Verpoort, J. R. A. Dann, D. Backes, C. J. B. Ford, M. Lanius, A. R. Jalil, P. Schüffelgen, G. Mussler, G. J. Conduit, D. Grützmacher. 2019-02-12. Long-lived non-equilibrium superconductivity in a non-centrosymmetric Rashba semiconductor. https://doi.org/10.1103/physrevb.100.024504

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