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Title: Features of the magnetic state of the layered Fe-V nanostructure of the superconductor-ferromagnet type

Abstract

The magnetic state of the V(39 nm)/20 [V(3 nm)/Fe(3 nm)] nanostructure has been investigated by polarized neutron reflectometry in the temperature range from 1.6 to 30 K in magnetic fields from 0.2 to 15 kOe. The data obtained indicate that the superconductivity of vanadium layers may affect magnetic ordering both over the depth of the structure and in its plane.

Authors:
 [1]; ;  [2];  [3];  [4];  [5]
  1. Russian Research Centre 'Kurchatov Institute' (Russian Federation)
  2. Joint Institute for Nuclear Research (Russian Federation)
  3. St. Petersburg State University, Universitetskaya nab. (Russian Federation)
  4. Joint Institute for Nuclear Research (Russian Federation), E-mail: khaiduk@nf.jinr.ru
  5. Ruhr-Universitaet Bochum (Germany)
Publication Date:
OSTI Identifier:
21090930
Resource Type:
Journal Article
Resource Relation:
Journal Name: Crystallography Reports; Journal Volume: 52; Journal Issue: 3; Other Information: DOI: 10.1134/S1063774507030054; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; IRON ALLOYS; LAYERS; MAGNETIC FIELDS; MAGNETIZATION; NANOSTRUCTURES; NEUTRONS; SUPERCONDUCTIVITY; SUPERCONDUCTORS; TEMPERATURE RANGE 0000-0013 K; TEMPERATURE RANGE 0013-0065 K; VANADIUM ALLOYS

Citation Formats

Aksenov, V. L., Nikitenko, Yu. V., Petrenko, A. V., Uzdin, V. M., Khaidukov, Yu. N., and Zabel, H. Features of the magnetic state of the layered Fe-V nanostructure of the superconductor-ferromagnet type. United States: N. p., 2007. Web. doi:10.1134/S1063774507030054.
Aksenov, V. L., Nikitenko, Yu. V., Petrenko, A. V., Uzdin, V. M., Khaidukov, Yu. N., & Zabel, H. Features of the magnetic state of the layered Fe-V nanostructure of the superconductor-ferromagnet type. United States. doi:10.1134/S1063774507030054.
Aksenov, V. L., Nikitenko, Yu. V., Petrenko, A. V., Uzdin, V. M., Khaidukov, Yu. N., and Zabel, H. Tue . "Features of the magnetic state of the layered Fe-V nanostructure of the superconductor-ferromagnet type". United States. doi:10.1134/S1063774507030054.
@article{osti_21090930,
title = {Features of the magnetic state of the layered Fe-V nanostructure of the superconductor-ferromagnet type},
author = {Aksenov, V. L. and Nikitenko, Yu. V. and Petrenko, A. V. and Uzdin, V. M. and Khaidukov, Yu. N. and Zabel, H.},
abstractNote = {The magnetic state of the V(39 nm)/20 [V(3 nm)/Fe(3 nm)] nanostructure has been investigated by polarized neutron reflectometry in the temperature range from 1.6 to 30 K in magnetic fields from 0.2 to 15 kOe. The data obtained indicate that the superconductivity of vanadium layers may affect magnetic ordering both over the depth of the structure and in its plane.},
doi = {10.1134/S1063774507030054},
journal = {Crystallography Reports},
number = 3,
volume = 52,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
  • Layered superconducting ferromagnetic nanosystems Cu(32 nm)/V(40-80 nm)/Fe(0.5-4 nm)/MgO(001) have been investigated by reflectometry and the diffuse scattering of synchrotron radiation. The data obtained make it possible to determine the important characteristics of samples such as the layer thickness and the rms heights and lateral correlation lengths of roughness at the interfaces.
  • The possibility of magnetic exchange coupling between two ferromagnets ({ital F}) separated by a superconductor ({ital S}) spacer is analyzed using the functional integral method. For this coupling to happen three basic conditions need to be satisfied. First, an indirect exchange coupling between the ferromagnets must exist when the superconductor is in its normal state. Second, superconductivity must not be destroyed due to the proximity to ferromagnetic boundaries. Third, roughness of the F/S interfaces must be small. The appearance of the superconducting gap causes a reduction of the indirect exchange coupling existent in the normal state. This reduction is temperaturemore » dependent, being weaker near the critical temperature and stronger at zero temperature. {copyright} {ital 1997} {ital The American Physical Society}« less
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