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Title: Two-dimensional surface magnetism in the bulk paramagnetic intermetallic alloy CoAl(100).

Abstract

Utilizing a combination of the in situ magneto-optical Kerr effect and scanning tunneling microscopy and spectroscopy measurements, we show that the (100) surface of the B2 bulk paramagnetic CoAl is an excellent representation of a two-dimensional ferromagnet. The order-parameter critical exponent {beta} = 0.22 {+-} 0.02 is determined, which is the universal signature of a finite-size two-dimensional XY behavior. The Curie temperature is found to be T{sub c} = 90 K. The magnetism can be explained by the appearance of Co antisite atoms at the surface.

Authors:
; ; ; ; ;  [1]
  1. (ISG-3).
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
943423
Report Number(s):
ANL/XSD/JA-57896
Journal ID: ISSN 0031-9007; PRLTAO; TRN: US200902%%195
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Phys. Rev. Lett.; Journal Volume: 98; Journal Issue: Jan. 17, 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
01 COAL, LIGNITE, AND PEAT; ALLOYS; ATOMS; COAL; CURIE POINT; KERR EFFECT; MAGNETISM; SCANNING TUNNELING MICROSCOPY; SPECTROSCOPY

Citation Formats

Rose, V., Bruggemann, K., David, R., Franchy, R., Center for Nanoscale Materials, and Institute for Surfaces and Interfaces. Two-dimensional surface magnetism in the bulk paramagnetic intermetallic alloy CoAl(100).. United States: N. p., 2007. Web. doi:10.1103/PhysRevLett.98.037202.
Rose, V., Bruggemann, K., David, R., Franchy, R., Center for Nanoscale Materials, & Institute for Surfaces and Interfaces. Two-dimensional surface magnetism in the bulk paramagnetic intermetallic alloy CoAl(100).. United States. doi:10.1103/PhysRevLett.98.037202.
Rose, V., Bruggemann, K., David, R., Franchy, R., Center for Nanoscale Materials, and Institute for Surfaces and Interfaces. Wed . "Two-dimensional surface magnetism in the bulk paramagnetic intermetallic alloy CoAl(100).". United States. doi:10.1103/PhysRevLett.98.037202.
@article{osti_943423,
title = {Two-dimensional surface magnetism in the bulk paramagnetic intermetallic alloy CoAl(100).},
author = {Rose, V. and Bruggemann, K. and David, R. and Franchy, R. and Center for Nanoscale Materials and Institute for Surfaces and Interfaces},
abstractNote = {Utilizing a combination of the in situ magneto-optical Kerr effect and scanning tunneling microscopy and spectroscopy measurements, we show that the (100) surface of the B2 bulk paramagnetic CoAl is an excellent representation of a two-dimensional ferromagnet. The order-parameter critical exponent {beta} = 0.22 {+-} 0.02 is determined, which is the universal signature of a finite-size two-dimensional XY behavior. The Curie temperature is found to be T{sub c} = 90 K. The magnetism can be explained by the appearance of Co antisite atoms at the surface.},
doi = {10.1103/PhysRevLett.98.037202},
journal = {Phys. Rev. Lett.},
number = Jan. 17, 2007,
volume = 98,
place = {United States},
year = {Wed Jan 17 00:00:00 EST 2007},
month = {Wed Jan 17 00:00:00 EST 2007}
}
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