Tuning the in-plane Fulde-Ferrell-Larkin-Ovchinnikov state in a superconductor/ferromagnet/normal-metal hybrid structure by current or magnetic field

Physical Review B: Condensed Matter and Materials Physics. 2018. Vol. 98. No. 21. P. 214510.

Marychev P., Водолазов Д. Ю.

Temperature-induced transition of thin superconductor/ferromagnet/normal-metal (S/F/N) hybrid structure to an in-plane Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state is accompanied by vanishing of effective inverse magnetic field penetration depth Λ−1. Here we show that Λ−1 goes to zero only in the limit of zero magnetic field H→0 and at any finite parallel H or in-plane current I it is finite and positive in the FFLO state, which implies a diamagnetic response. We demonstrate that Λ−1 has a nonmonotonic dependence on H and I not only in the parameter range corresponding to the FFLO phase domain but also in its vicinity. We find that for S/F/N/F/S structures with certain thicknesses of F layers there is a temperature-, current-, and magnetic-field-driven transition to and out of the FFLO phase with a simultaneous jump of Λ−1.

Keywords: proximity effect, superconducting hybrid structures, эффект близости, сверхпроводниковые гибридные структуры