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Cryptoferromagnetic state in superconductor-ferromagnet multilayers

F. S. Bergeret·K. B. Efetov·A. I. Larkin
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Abstract

We study a possibility of a non-homogeneous magnetic order (cryptoferromagnetic state) in heterostructures consisting of a bulk superconductor and a ferromagnetic thin layer that can be due to the influence of the superconductor. The exchange field in the ferromagnet may be strong and exceed the inverse mean free time. A new approach based on solving the Eilenberger equations in the ferromagnet and the Usadel equations in the superconductor is developed. We derive a phase diagram between the cryptoferromagnetic and ferromagnetic states and discuss the possibility of an experimental observation of the CF state in different materials.

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F. S. Bergeret, K. B. Efetov, A. I. Larkin. 2000-02-10. Cryptoferromagnetic state in superconductor-ferromagnet multilayers. https://doi.org/10.1103/physrevb.62.11872

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