Critical temperature oscillations and reentrant superconductivity due to the FFLO like state in F/S/F trilayers

Abstract

Ferromagnet/Superconductor/Ferromagnet (F/S/F) trilayers, in which the establishing of a

Experimental observation of the triplet spin-valve effect in a superconductor-ferromagnet heterostructure

“…scenario (iii)) The S/F 1 /F 2 core, compared with the F 1 /S/F 2 or F 1 /S/F 1 cores design [29][30][31], allows not only T c for the parallel (P) alignment to be lower than for the antiparallel (AP) alignment of the F 1 and F 2 magnetic moments (T c P < T c AP -the "direct" spin-valve effect), but also the opposite (T c AP < T c P -the "inverse" spin-valve effect). Moreover, a non-monotonic dependence of the superconducting transition temperature T c on the angle between the magnetic moments of the adjacent ferromagnetic layers, F 1 and F 2 , and the "triplet" spin-valve effect was predicted [17], at which T c TR for the NCA of magnetic moments is the absolute minimum T c , because T c TR < {T c AP ,T c P }.…”

Tailoring the Fulde‐Ferrell‐Larkin‐Ovchinnikov state

“…Now scale that down by a factor of 10 5 -to 80 mm times 7 mm, and correspondingly its thickness to 10 nm, and you have an idea about the precision and control necessary to create thin films in experiments like the one published recently in Annalen der Physik by Jan-Michael Kehrle and co-workers [1]. The motivation for creating such extraordinarily thin films over comparatively large areas was a prediction that if a thin layer of a conventional superconductor is sandwiched between two ferromagnetic films, then the superconducting transition temperature of this trilayer structure, after initially being suppressed, would show a reentrance behaviour when the thickness of one or both of the ferromagnetic layers is varied.…”

“…Motivated by experimental results from 1986 on V/Fe superlattices by Hong-Kuen Wong et al in the group of John Ketterson at Northwestern University [5], early theoretical work was provided by Alexander Buzdin and Mikhail Kupriyanov (Moscow State University) [6], by Zoran Radović (Institute of Physics, Belgrade) and co-workers (Ref. 18 in [1]), and by Lenar Tagirov (Kazan State University), who in particular developed a theory for the phenomenon of re-entrant superconductivity in such systems (Refs. 20 and 25 in [1]).…”

“…18 in [1]), and by Lenar Tagirov (Kazan State University), who in particular developed a theory for the phenomenon of re-entrant superconductivity in such systems (Refs. 20 and 25 in [1]). Extension of the theory beyond the diffusive limit was the focus of Yakov Fominov and Nikolai Chtchelkachev from the Landau Institute for Theoretical Physics in Chernogolovka, and Alexander Golubov from University of Twente [7].…”

“…A magnetron sputtering device designed and patented by Anatoli Sidorenko, Vladimir Zdravkov, and Roman Morari (Refs. 21, 22, and 43 in [1]) from the Institute of Electronic Engineering and Nanotechnologies in Kishinev, allowed for the production of entire batches of samples with different (and controlled) layer thicknesses under literally identical conditions. The device is shown in panel b) of Fig.…”