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Title: Electronic Structure of Halogen Doped CuCr2Se4

Abstract

We have employed element and chemically sensitive X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) in order to address a long standing controversy regarding the electronic and magnetic state of CuCr{sub 2}Se{sub 4} via halogen doping of the Se anion site in CuCr{sub 2}Se{sub 4-x}Y{sub x} (Y=Cl and Br). Long range magnetic order is observed above room temperature for all samples. The Cr L{sub 2,3} XAS spectra show a prevalent 3+ valence for the Cr ions independent of doping concentration and doping agent. The Cu L{sub 2,3} XAS spectra show a combination of 1+ and 2+ valence states for all samples. XMCD spectra indicate the presence of a magnetic moment associated with the Cu ions that is aligned antiparallel to the Cr moment.

Authors:
; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
Advanced Light Source Division
OSTI Identifier:
925857
Report Number(s):
LBNL-106E
Journal ID: ISSN 0021-8979; JAPIAU; TRN: US0802532
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics
Country of Publication:
United States
Language:
English
Subject:
75; ABSORPTION SPECTROSCOPY; ANIONS; ELECTRONIC STRUCTURE; HALOGENS; MAGNETIC CIRCULAR DICHROISM; MAGNETIC MOMENTS; SPECTRA; VALENCE; halogen doped CuCr2Se4 XMCD XAS

Citation Formats

Arenholz, Elke, Liberati, M., Neulinger, J. R., Chopdekar, R.V., Bettinger, J.S., Arenholz, E., Butler, W., Stacy, A.M., Idzerda, Y.I., and Suzuki, Y. Electronic Structure of Halogen Doped CuCr2Se4. United States: N. p., 2008. Web.
Arenholz, Elke, Liberati, M., Neulinger, J. R., Chopdekar, R.V., Bettinger, J.S., Arenholz, E., Butler, W., Stacy, A.M., Idzerda, Y.I., & Suzuki, Y. Electronic Structure of Halogen Doped CuCr2Se4. United States.
Arenholz, Elke, Liberati, M., Neulinger, J. R., Chopdekar, R.V., Bettinger, J.S., Arenholz, E., Butler, W., Stacy, A.M., Idzerda, Y.I., and Suzuki, Y. Sat . "Electronic Structure of Halogen Doped CuCr2Se4". United States. doi:. https://www.osti.gov/servlets/purl/925857.
@article{osti_925857,
title = {Electronic Structure of Halogen Doped CuCr2Se4},
author = {Arenholz, Elke and Liberati, M. and Neulinger, J. R. and Chopdekar, R.V. and Bettinger, J.S. and Arenholz, E. and Butler, W. and Stacy, A.M. and Idzerda, Y.I. and Suzuki, Y.},
abstractNote = {We have employed element and chemically sensitive X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) in order to address a long standing controversy regarding the electronic and magnetic state of CuCr{sub 2}Se{sub 4} via halogen doping of the Se anion site in CuCr{sub 2}Se{sub 4-x}Y{sub x} (Y=Cl and Br). Long range magnetic order is observed above room temperature for all samples. The Cr L{sub 2,3} XAS spectra show a prevalent 3+ valence for the Cr ions independent of doping concentration and doping agent. The Cu L{sub 2,3} XAS spectra show a combination of 1+ and 2+ valence states for all samples. XMCD spectra indicate the presence of a magnetic moment associated with the Cu ions that is aligned antiparallel to the Cr moment.},
doi = {},
journal = {Journal of Applied Physics},
number = ,
volume = ,
place = {United States},
year = {Sat Sep 13 00:00:00 EDT 2008},
month = {Sat Sep 13 00:00:00 EDT 2008}
}
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