Eur. Phys. J. B 30, 33-38 (2002)
https://doi.org/10.1140/epjb/e2002-00354-y

Coexistence of superconductivity and ferromagnetism in ferromagnet/superconductor proximity structures

¹ National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, PR China
² Department of Physics, The Chinese University of Hong Kong, Hong Kong, PR China

Corresponding author: ^a dyxing@nju.edu.cn

Received: 1 July 2002
Published online: 19 November 2002

Abstract

The Nambu spinor Green's function approach is applied to calculating the density of states (DOS) and superconducting order parameter in normal-metal/insulator/ferromagnet/superconductor (NM/I/FM/SC) junctions. It is found that the s-wave superconductivity and ferromagnetism can coexist near the FM/SC interface, which is induced by proximity effect. On the SC side, the spin-dependent DOS appears both within and without the energy gap. On the FM side, the superconducting order parameter displays a damped oscillation and the DOS exhibits some superconducting behavior. The calculated result for the DOS in FM for “0 state” and “π state” can reproduce recent tunneling spectra in Al/Al₂O₃/PdNi/Nb tunnel junctions.