- Презентация доклада о современном состоянии в тороидных метаматериалах.
- Представление последних результатов исследований Лаборатории «Сверхпроводящие метаматериалы» в области тороидных метаматериалов;
- Презентации докладов
об исследованиях планарных и диэлектрических метаматериалов;
Aymen BEN HAMIDA
National University of Science and Technology “MISiS”
Spatial oscillations and nonuniform superconductivity in hybrid multilayered structures
Superconductivity and ferromagnetism are two competing spin orders. Their coexistence is only possible in a narrow interval of parameters, for example, when a superconductor (S) and a ferromagnetic metal (F) are brought in an electric contact in superconductor-ferromagnet layered structures. It turns out that superconductivity and magnetism can interact and influence each other in the vicinity of the boundary. We call these phenomena proximity effects in S/F structures.
During the last two decades, much attention has been paid to the properties of hybrid proximity systems containing superconductors and ferromagnets. New physical phenomena were observed and predicted in these systems. The most important from them, that the exponential decay of the superconducting condensate amplitude into ferromagnets is accompanied by oscillations in space. These oscillations lead, for example, to oscillations of the critical superconducting temperature Tc and the critical Josephson current Ic in SFS structures as a function of the thickness dF of the ferromagnet. Due to this oscillatory behavior, the critical Josephson current should change its sign in a SFS junction (π-junction). This phenomenon has been confirmed experimentally in Ref. [1,2].
In this talk, a review of the proximity effect in SF bilayers and SFS structures will be given, as well as experimental results of the 0- π transition obtained in the group on Nb/CuNi and Nb/PdFe structures.
 V. V. Ryazanov et al., Phys. Rev. Lett. 86, 2427 (2001).
 V. A. Oboznov et al., Phys. Rev. Lett. 96, 197003 (2006).