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Title: Field-induced domain wall motion of amorphous [CoSiB/Pt]{sub N} multilayers with perpendicular anisotropy

Amorphous CoSiB/Pt multilayer is a perpendicular magnetic anisotropy material to achieve high squareness, low coercivity, strong anisotropy, and smooth domain wall (DW) motion, because of the smoother interface compared with crystalline multilayers. For [CoSiB(6 Å)/Pt (14 Å)]{sub N} multilayers with N = 3, 6, and 9, we studied the field-induced DW dynamics. The effective anisotropy constant K{sub 1}{sup eff} is 1.5 × 10{sup 6} erg/cm{sup 3} for all the N values, and the linear increment of coercive field H{sub c} with N gives constant exchange coupling J. By analyzing the field dependence of DW images at room temperature, a clear creep motion with the exponent μ = 1/4 could be observed. Even though the pinning field H{sub dep} slightly increases with N, the pinning potential energy U{sub c} is constant (=35 k{sub B}T) for all the N values. These results imply that the amorphous [CoSiB/Pt]{sub N} multilayers are inherently homogeneous compared to crystalline multilayers. For N ≤ 6, the pinning site density ρ{sub pin} is less than 1000/μm{sup 2}, which is about 1 pinning site per the typical device junction size of 30 × 30 nm{sup 2}. Also, the exchange stiffness constant A{sub ex} is obtained to be 0.48 × 10{sup −6} erg/cm, and the domain wall width is expected to be smaller than 5.5 nm. Thesemore » results may be applicable for spin-transfer-torque magnetic random access memory and DW logic device applications.« less
Authors:
; ;  [1] ; ; ;  [2] ;  [3]
  1. Department of Physics, Sogang University, Seoul 121-742 (Korea, Republic of)
  2. Department of Physics, Inha University, Incheon 402-751 (Korea, Republic of)
  3. Department of Advanced Materials Engineering, Sejong University, Seoul 143-747 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22275570
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 18; 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; ANISOTROPY; COBALT COMPOUNDS; COERCIVE FORCE; COMPARATIVE EVALUATIONS; COUPLING; CREEP; DOMAIN STRUCTURE; ELECTRIC CONTACTS; FLEXIBILITY; INTERFACES; LAYERS; PLATINUM; POTENTIAL ENERGY; SEMICONDUCTOR JUNCTIONS; SILICON BORIDES; TEMPERATURE RANGE 0273-0400 K