Dresden 2020 – wissenschaftliches Programm
Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...
TT 55.3: Vortrag
Donnerstag, 19. März 2020, 10:15–10:30, HSZ 204
Phase-dependent spin polarization of Cooper pairs in magnetic Josephson junctions — •Samme M. Dahir, Anatoly F. Volkov, and Ilya M. Eremin — Institut für Theoretische Physik III, Ruhr-Universität Bochum, D-44780 Bochum, Germany
Superconductor-ferromagnet hybrid structures (SF) have attracted much interest in the past decades, due to a variety of interesting phenomena predicted and observed in these structures. One of them is the so-called inverse proximity effect. It is described by a spin polarization of Cooper pairs, which occurs not only in the ferromagnet (F), but also in the superconductor (S), yielding a finite magnetic moment MS inside the superconductor. This effect has been predicted and experimentally studied. However, interpretation of the experimental data is mostly ambiguous. Here, we study theoretically the impact of the spin polarized Cooper pairs on the Josephson effect in an SFS junction. We show that the induced magnetic moment MS does depend on the phase difference ϕ and, therefore, will oscillate in time with the Josephson frequency 2eV/ℏ if the current exceeds a critical value. Most importantly, the spin polarization in the superconductor causes a significant change in the Fraunhofer pattern, which can be easily accessed experimentally.