English

Odd triplet superconductivity in clean and moderately disordered SFFS junctions

Superconductivity 2009-07-14 v1 Mesoscale and Nanoscale Physics

Abstract

We study the Josephson effect and pairing correlations in SFFS junctions that consist of conventional superconductors (S) connected through two metallic monodomain ferromagnets (F) with transparent and spin inactive interfaces. We solve the Eilenberger equations for arbitrary relative orientation of magnetizations of the two F layers in the clean limit and for moderate disorder in ferromagnets. Spatial variation of pair amplitudes, singlet fsf_s, and odd in frequency triplet ft0f_{t0} and ft1f_{t1}, with 0 and ±1\pm1 spin projections, as well as the Josephson current-phase relations are calculated for different values of the ferromagnetic layers thickness and angle α\alpha between in-plane magnetizations. In contrast to the dirty limit case, we find that for 0<α<π0<\alpha<\pi both spin singlet and triplet pair amplitudes in F layers power-law decay in the same oscillatory manner with distance from the FS interfaces. This decay gets faster as the impurity-scattering rate in ferromagnets is increased. The computed triplet amplitude ft1f_{t1} has opposite signs in the two magnet regions, penetrates into the superconductors and monotonically decays over the same distance, which is the superconducting coherence length, as the singlet amplitude fsf_s saturates to the bulk value. We point out that influence of misorientation of magnetizations on the Josephson current can not be attributed directly to the appearance of odd triplet correlations.

Keywords

Cite

@article{arxiv.0907.2042,
  title  = {Odd triplet superconductivity in clean and moderately disordered SFFS junctions},
  author = {Zorica Popović and Zoran Radović},
  journal= {arXiv preprint arXiv:0907.2042},
  year   = {2009}
}

Comments

9 pages, 13 figures

R2 v1 2026-06-21T13:24:05.952Z