Multicritical behavior of the phase diagrams of ferromagnet/superconductor layered structures

Pleiades Publishing Ltd - Tập 71 - Trang 138-143 - 2000
Yu. A. Izyumov1, Yu. N. Proshin2, M. G. Khusainov3
1Institute of Metal Physics, Ural Division, Russian Academy of Sciences, Yekaterinburg, Russia
2Kazan State University, Kazan, Russia
3Kazan State Technical University, Vostok Branch, Chistopol’, Russia

Tóm tắt

For ferromagnet/superconductor (F/S) layered structures, new 3D Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) states are predicted. In most cases, these states are characterized by a higher critical temperature T c than the known 1D LOFF states. It is shown that the nonmonotonic behavior of T c is determined by the oscillations of the Cooper pair flux through the F/S boundary, which occur as a result of the 3D-1D-3D phase transitions at the Lifshits triple points. The appearance of the new 3D LOFF states and the presence of nonmagnetic impurities leads to a strong damping of the 1D oscillations of the LOFF pair amplitude and to a considerable smoothing of the dependence of T c on the F layer thickness d f . An interpretation of the behavior of the experimental dependences T c (d f ) obtained for F/S structures is proposed.

Tài liệu tham khảo

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