Odd triplet superconductivity in a superconductor/ferromagnet structure with a narrow domain wall
Abstract
We study proximity effect in superconductor/ferromagnet (SF) structure with a narrow domain wall (DW) at the SF interface. The width of the domain wall is assumed to be larger than the Fermi wavelength but smaller than other characteristic lengths (for example, the “magnetic” length). The transmission coefficient is supposed to be small so that we deal with a weak proximity effect. Solving the linearized Eilenberger equation, we find analytical expressions for quasiclassical Green’s functions. These functions describe the shortrange (SR) condensate components, singlet and triplet, with zero projection of the total spin on the quantization z axis, induced in ferromagnet (F) due to the proximity effect as well as longrange odd triplet component (LRTC) with a nonzero projection of the total spin of Cooper pairs on the z axis. The amplitude of the LRTC essentially depends on the product hτ and increases with increasing the exchange energy h ( τ is the elasticscattering time). We calculate the Josephson current in superconductor/ferromagnet/superconductor junction with a thickness of the F layer much greater than the penetration length of the SR components. The Josephson critical current caused by the LRTC may be both positive and negative depending on chirality of the magnetic structure in F. The density of states (DOS) in a diffusive SF bilayer is also analyzed. It is shown that the contributions of the SR and LR components to the DOS in F have a different dependence on the thickness d of the F layer (nonmonotonous and monotonous).
 Publication:

Physical Review B
 Pub Date:
 July 2008
 DOI:
 10.1103/PhysRevB.78.024519
 arXiv:
 arXiv:0802.3151
 Bibcode:
 2008PhRvB..78b4519V
 Keywords:

 74.45.+c;
 74.50.+r;
 74.90.+n;
 Proximity effects;
 Andreev effect;
 SN and SNS junctions;
 Tunneling phenomena;
 point contacts weak links Josephson effects;
 Other topics in superconductivity;
 Condensed Matter  Superconductivity;
 Condensed Matter  Mesoscale and Nanoscale Physics
 EPrint:
 14 pages, 3 Figs. submitted to Phys. Rev. B