Interelectronic interaction in dirty FS trilayers: A manifestation of “hidden” superconductivity

How experimentally to detect a solitary superconductivity in dirty ferromagnet-superconductor trilayers?

“…We also discuss its of the spin valve applications. As was mentioned above the solitary superconductivity in FFS system may be observed only in the AP state [7,8,9]. In order to prepare state with a well-defined solitary superconductivity experimentalists should adhere to the following algorithm.…”

“…As was mentioned above, such an extraordinary nonmonotonic dependence T c (d f 2 ) is called solitary superconductivity. Note again that for the parallel state, the system is always in the resistive state [7,8,9] and hence, the difference ∆T = T AP c − T P c ≡ T AP c is a maximal. The physical reason for this phenomenon is simple: the exchange field of the intermediate F 2 layer, which is a strong depairing factor for the superconducting state, is partially compensated at AP state, herewith the "effective" exchange field becomes smaller and superconductivity appears.…”

“…The physical reason for this phenomenon is simple: the exchange field of the intermediate F 2 layer, which is a strong depairing factor for the superconducting state, is partially compensated at AP state, herewith the "effective" exchange field becomes smaller and superconductivity appears. For more complete compensations of the effective exchange field the soft magnetic materials with low Curie temperature (such as Ni 1−x Cu x or Pr) alloys should be used for both F layers [7,8,9].…”

“…For strong ferromagnets such as Fe, Ni or Co the decay depth is approximately few nanometers. The peculiarity of the FS proximity effect and interplay between the S and F parameter orders give rise to a number of interesting phenomena and effects (see reviews [2,3,4] and the references therein), for example, the reentrant [5,6,7] and solitary superconductivity [8,9], nonmonotonic behaviors of the critical temperature T c as function of the mutual alignment of the magnetizations of the F layers [10,11] and so on.…”

“…Earlier we theoretically investigate a solitary superconductivity for F 1 F 2 S system [7,8,9]. The solitary superconductivity corresponds to a localized region on the phase diagram of T c (d f ), in which T c > 0 and thickness…”