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Title: Spin-triplet electron transport in hybrid superconductor heterostructures with a composite ferromagnetic interlayer

Abstract

Hybrid YBa{sub 2}Cu{sub 3}O{sub 7−x}/SrRuO{sub 3}/La{sub 0.7}Sr{sub 0.3}MnO{sub 3}/Au-Nb superconductor mesastructures with a composite manganite-ruthenate ferromagnetic interlayer are studied using electrophysical, magnetic, and microwave methods. The supercurrent in the mesastructure is observed when the interlayer thickness is much larger than the coherence length of ferromagnetic materials. The peak on the dependence of the critical current density on the interlayer material thickness corresponds to the coherence length, which is in qualitative agreement with theoretical predictions for a system with spit-triplet superconducting correlations. The magnetic-field dependence of the critical current is determined by penetration of magnetic flux quanta and by the magnetic domain structure, as well as by the field dependence of disorientation of the magnetization vectors of the layers in the composite magnetic interlayer. It is found that the supercurrent exists in magnetic fields two orders of magnitude stronger than the field corresponding to entry of a magnetic flux quantum into the mesastructure. The current-phase relation (CPR) of the supercurrent of mesastructures is investigated upon a change in the magnetic field from zero to 30 Oe; the ratio of the second CPR harmonic to the first, determined from the dependence of the Shapiro steps on the microwave radiation amplitude, does notmore » exceed 50%.« less

Authors:
; ; ; ;  [1];  [2];  [3]
  1. Russian Academy of Sciences, Kotelnikov Institute of Radio Engineering and Electronics (Russian Federation)
  2. Chalmers University of Technology (Sweden)
  3. Max-Planck Institute for Solid State Research (Germany)
Publication Date:
OSTI Identifier:
22472220
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 120; Journal Issue: 6; Other Information: Copyright (c) 2015 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; BARIUM COMPOUNDS; COHERENCE LENGTH; CORRELATIONS; CRITICAL CURRENT; CUPRATES; DOMAIN STRUCTURE; ELECTRONS; FERROMAGNETIC MATERIALS; GOLD; LANTHANUM COMPOUNDS; MAGNETIC FIELDS; MAGNETIC FLUX; MAGNETIZATION; MANGANATES; MICROWAVE RADIATION; NIOBIUM; RUTHENIUM OXIDES; STRONTIUM COMPOUNDS; SUPERCONDUCTORS; YTTRIUM COMPOUNDS

Citation Formats

Sheyerman, A. E., E-mail: karen@hitech.cplire.ru, Constantinian, K. Y., Ovsyannikov, G. A., Kislinskii, Yu. V., Shadrin, A. V., Kalabukhov, A. V., and Khaydukov, Yu. N.. Spin-triplet electron transport in hybrid superconductor heterostructures with a composite ferromagnetic interlayer. United States: N. p., 2015. Web. doi:10.1134/S1063776115050192.
Sheyerman, A. E., E-mail: karen@hitech.cplire.ru, Constantinian, K. Y., Ovsyannikov, G. A., Kislinskii, Yu. V., Shadrin, A. V., Kalabukhov, A. V., & Khaydukov, Yu. N.. Spin-triplet electron transport in hybrid superconductor heterostructures with a composite ferromagnetic interlayer. United States. doi:10.1134/S1063776115050192.
Sheyerman, A. E., E-mail: karen@hitech.cplire.ru, Constantinian, K. Y., Ovsyannikov, G. A., Kislinskii, Yu. V., Shadrin, A. V., Kalabukhov, A. V., and Khaydukov, Yu. N.. Mon . "Spin-triplet electron transport in hybrid superconductor heterostructures with a composite ferromagnetic interlayer". United States. doi:10.1134/S1063776115050192.
@article{osti_22472220,
title = {Spin-triplet electron transport in hybrid superconductor heterostructures with a composite ferromagnetic interlayer},
author = {Sheyerman, A. E., E-mail: karen@hitech.cplire.ru and Constantinian, K. Y. and Ovsyannikov, G. A. and Kislinskii, Yu. V. and Shadrin, A. V. and Kalabukhov, A. V. and Khaydukov, Yu. N.},
abstractNote = {Hybrid YBa{sub 2}Cu{sub 3}O{sub 7−x}/SrRuO{sub 3}/La{sub 0.7}Sr{sub 0.3}MnO{sub 3}/Au-Nb superconductor mesastructures with a composite manganite-ruthenate ferromagnetic interlayer are studied using electrophysical, magnetic, and microwave methods. The supercurrent in the mesastructure is observed when the interlayer thickness is much larger than the coherence length of ferromagnetic materials. The peak on the dependence of the critical current density on the interlayer material thickness corresponds to the coherence length, which is in qualitative agreement with theoretical predictions for a system with spit-triplet superconducting correlations. The magnetic-field dependence of the critical current is determined by penetration of magnetic flux quanta and by the magnetic domain structure, as well as by the field dependence of disorientation of the magnetization vectors of the layers in the composite magnetic interlayer. It is found that the supercurrent exists in magnetic fields two orders of magnitude stronger than the field corresponding to entry of a magnetic flux quantum into the mesastructure. The current-phase relation (CPR) of the supercurrent of mesastructures is investigated upon a change in the magnetic field from zero to 30 Oe; the ratio of the second CPR harmonic to the first, determined from the dependence of the Shapiro steps on the microwave radiation amplitude, does not exceed 50%.},
doi = {10.1134/S1063776115050192},
journal = {Journal of Experimental and Theoretical Physics},
number = 6,
volume = 120,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}
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