Reentrance phenomenon in superconductor/ferromagnet nanostructures and their application in superconducting spin valves for superconducting electronics

• Main Author: Sidorenko, A.S.
• Format: Article
• Language: English
• Published: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2017
• Series: Физика низких температур
• Subjects: Сверхпроводящие и мезоскопические структуры. К 70-летию со дня рождения А.Н. Омельянчука
• Online Access: http://dspace.nbuv.gov.ua/handle/123456789/129527

In superconductor/ferromagnet layered structures, a Fulde–Ferrell–Larkin–Ovchinnikov-like inhomogeneous superconducting pairing give rise. The singlet and zero-projection triplet components of the pairing oscillate in space, and the presence of interfaces causes interference phenomena. As the result of the interference, the super-conducting critical temperature Tc oscillates as a function of the ferromagnetic layer thicknesses or, even more spectacular, reentrant superconductivity appears. Two ferromagnetic layers can be combined with a superconducting layer into a superconducting spin valve. Proper design and choice of the material parameters give possibility to control superconducting Tc manipulating with magnetic configurations in the system. The conditions to get large spin-valve effect, i.e., a large shift in the critical temperature, are reviewed in the article.