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Title: Growth induced magnetic anisotropy in amorphous thin films. Annual progress report year 1, November 4, 1994--October 31, 1995

Abstract

The work in the past year has primarily involved three areas of magnetic thin films: amorphous rare earth-transition metal alloys, epitaxial COPt3 thin films, and exchange coupled antiferromagnetic insulators. In the amorphous alloys, the authors have focused on understanding the cause and the effect of the growth-surface-induced perpendicular magnetic anisotropy. Using the results of previous work, they are able to control this anisotropy quite precisely. This anisotropy is predicted to have dramatic and as-yet unobserved effects on the underlying nature of the magnetism. The work on the epitaxial Co-Pt alloys was originally undertaken as a comparison study to the amorphous alloys. The authors have discovered that these alloys exhibit a remarkable new phenomena; a surface-induced miscibility gap in a material which is believed to be completely miscible in the bulk. This miscibility gap is 100% correlated with the perpendicular anisotropy, although the connection is not yet clear, and is presumably linked to a magnetic energy of mixing which tends to drive a material towards clustering. The problem of exchange coupling in multilayers impacts many of the current research areas in magnetism. NiO/CoO multilayers can be prepared with coherent interfaces. The specific heat shows unambiguously the ordering of the spins inmore » the layers. The results show clearly the transition from a single transition temperature to two distinct transitions with increasing thickness of the individual layers. From this data, the authors are able to determine the interface magnetic exchange coupling constant and the effect on the transition temperature of finite layer thickness.« less

Authors:
 [1]
  1. Univ. of California, San Diego, La Jolla, CA (United States). Dept. of Physics
Publication Date:
Research Org.:
California Univ., San Diego, La Jolla, CA (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
86991
Report Number(s):
DOE/ER-45529; CONF-950380-2
ON: DE95015362; TRN: AHC29521%%47
DOE Contract Number:  
FG03-95ER45529
Resource Type:
Technical Report
Resource Relation:
Conference: Annual meeting of the Division of High Polymer Physics of the American Physical Society, San Jose, CA (United States), 20-24 Mar 1995; Other Information: PBD: [1995]
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COBALT ALLOYS; MAGNETIC PROPERTIES; PLATINUM ALLOYS; NICKEL OXIDES; COBALT OXIDES; RARE EARTH ALLOYS; TRANSITION ELEMENT ALLOYS; PROGRESS REPORT; ANISOTROPY; AMORPHOUS STATE; ANTIFERROMAGNETIC MATERIALS; SCATTERING; PHASE TRANSFORMATIONS

Citation Formats

Hellman, F. Growth induced magnetic anisotropy in amorphous thin films. Annual progress report year 1, November 4, 1994--October 31, 1995. United States: N. p., 1995. Web. doi:10.2172/86991.
Hellman, F. Growth induced magnetic anisotropy in amorphous thin films. Annual progress report year 1, November 4, 1994--October 31, 1995. United States. https://doi.org/10.2172/86991
Hellman, F. 1995. "Growth induced magnetic anisotropy in amorphous thin films. Annual progress report year 1, November 4, 1994--October 31, 1995". United States. https://doi.org/10.2172/86991. https://www.osti.gov/servlets/purl/86991.
@article{osti_86991,
title = {Growth induced magnetic anisotropy in amorphous thin films. Annual progress report year 1, November 4, 1994--October 31, 1995},
author = {Hellman, F},
abstractNote = {The work in the past year has primarily involved three areas of magnetic thin films: amorphous rare earth-transition metal alloys, epitaxial COPt3 thin films, and exchange coupled antiferromagnetic insulators. In the amorphous alloys, the authors have focused on understanding the cause and the effect of the growth-surface-induced perpendicular magnetic anisotropy. Using the results of previous work, they are able to control this anisotropy quite precisely. This anisotropy is predicted to have dramatic and as-yet unobserved effects on the underlying nature of the magnetism. The work on the epitaxial Co-Pt alloys was originally undertaken as a comparison study to the amorphous alloys. The authors have discovered that these alloys exhibit a remarkable new phenomena; a surface-induced miscibility gap in a material which is believed to be completely miscible in the bulk. This miscibility gap is 100% correlated with the perpendicular anisotropy, although the connection is not yet clear, and is presumably linked to a magnetic energy of mixing which tends to drive a material towards clustering. The problem of exchange coupling in multilayers impacts many of the current research areas in magnetism. NiO/CoO multilayers can be prepared with coherent interfaces. The specific heat shows unambiguously the ordering of the spins in the layers. The results show clearly the transition from a single transition temperature to two distinct transitions with increasing thickness of the individual layers. From this data, the authors are able to determine the interface magnetic exchange coupling constant and the effect on the transition temperature of finite layer thickness.},
doi = {10.2172/86991},
url = {https://www.osti.gov/biblio/86991}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 1995},
month = {Sat Jul 01 00:00:00 EDT 1995}
}