Density of states in the presence of spin-dependent scattering in SF bilayers: a numerical and analytical approach

Beilstein J Nanotechnol. 2022 Dec 1:13:1418-1431. doi: 10.3762/bjnano.13.117. eCollection 2022.

Abstract

We present a quantitative study of the density of states (DOS) in SF bilayers (where S is a bulk superconductor and F is a ferromagnetic metal) in the diffusive limit. We solve the quasiclassical Usadel equations in the structure considering the presence of magnetic and spin-orbit scattering. For practical reasons, we propose the analytical solution for the density of states in SF bilayers in the case of a thin ferromagnet and low transparency of the SF interface. This solution is confirmed by numerical calculations using a self-consistent two-step iterative method. The behavior of DOS dependencies on magnetic and spin-orbit scattering times is discussed.

Keywords: Josephson junctions; density of states; proximity effect; superconductivity; superconductor/ferromagnet hybrid nanostructures.

Grants and funding

The numerical calculations of the density of states in S/F bilayers (see Figures 2–6) were supported by the Mirror Laboratories Project of HSE University. The analytical calculations of the density of states in S/F bilayers (see Figure 7 and Figure 9) were supported by the RSF project No. 20-42-09033. The calculations of the current-voltage characteristics of the SFIFS Josephson junctions (see Figure 8) were supported by the Foundation for the Advancement of Theoretical Physics and Mathematics "BASIS".