Enhancement of the Josephson current by magnetic field in superconducting tunnel structures with a paramagnetic spacer

• Published in: Физика низких температур
• Date: 2005
• ISSN: 0132-6414
• Main Authors: Krivoruchko, V.N., Koshina, E.A.
• Format: Article
• Language: Russian
• Published: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2005
• Subjects: Свеpхпpоводимость, в том числе высокотемпеpатуpная
• Online Access: https://nasplib.isofts.kiev.ua/handle/123456789/121390
• Journal Title: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Cite this: Enhancement of the Josephson current by magnetic field in superconducting tunnel structures with a paramagnetic spacer / V.N. Krivoruchko, E.A. Koshina // Физика низких температур. — 2005. — Т. 31, № 2. — С. 164-168. — Бібліогр.: 24 назв. — англ.

The dc Josephson critical current of a (S/M)IS tunnel structure in a parallel magnetic field is
 investigated (here S is a superconductor, S/M is a proximity-coupled S and paramagnetic metal M
 bilayer, and I is an insulating barrier). We consider the case when, due to Hund’s rule, in the
 metal M the effective molecular interaction aligns the spins of the conduction electrons
 antiparallel to the localized spins of magnetic ions. It is predicted that for the tunnel structures
 under consideration there are conditions such that the destructive action of the internal and the
 applied magnetic fields on Cooper pairs is weakened, and increase of the applied magnetic field
 causes field-induced enhancement of the critical tunnel current. The experimental realization of
 this interesting effect of the interplay between superconductivity and magnetism is also discussed.