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Title: Study on the occurrence of spontaneously established perpendicular exchange bias in Co{sub 49}Pt{sub 51}/IrMn bilayers

In this study, perpendicular exchange bias (PEB) effect in the as-grown Co{sub 49}Pt{sub 51}/IrMn bilayers was demonstrated at room temperature using single-layered Co{sub 49}Pt{sub 51} alloy thin film as ferromagnetic (FM) layer. Several unusual features were observed in this system, viz.,: (i) the PEB was spontaneously established without any external magnetic field treatments, (ii) single-shifted loops were obtained rather than double-shifted ones, and (iii) the spontaneous PEB effect was accompanied by a reduction in perpendicular coercivity, H{sub c⊥} from 1024 to 632 Oe. The results of x–ray diffraction revealed the formation of IrMn (111) texture. Training effect studies indicate that the PEB effect is stable in this system with less than 5% variation in PEB value within 15 repetitive scans. Significant reduction in the PEB effect was found for the CoPt/IrMn films either grown or subjected to post-annealing under external magnetic field (H{sub ind}). The thickness dependence of PEB effect with respect to the FM and antiferromagnetic layers were also investigated and a largest PEB value of 533 Oe was obtained for the sample grown with 3-nm thick CoPt and 10-nm thick IrMn layers. The results of present study thus establish an opportunity to realize PEB effect in the absence of externalmore » field during fabrication.« less
Authors:
;  [1] ;  [2] ;  [2] ;  [3]
  1. Graduate Institute of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan (China)
  2. Department of Physics, National Taiwan University, Taipei 106, Taiwan (China)
  3. (India)
Publication Date:
OSTI Identifier:
22273734
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 17; Conference: 55. annual conference on magnetism and magnetic materials, Atlanta, GA (United States), 14-18 Nov 2010; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; ANNEALING; ANTIFERROMAGNETISM; COBALT ALLOYS; COERCIVE FORCE; CRYSTAL STRUCTURE; FERROMAGNETIC MATERIALS; INTERFACES; IRIDIUM ALLOYS; LAYERS; MAGNETIC FIELDS; MANGANESE ALLOYS; PLATINUM ALLOYS; TEMPERATURE RANGE 0273-0400 K; THIN FILMS; X-RAY DIFFRACTION