Abstract

Angular-dependent channeling Rutherford backscattering spectroscopy (c-RBS) has been used to quantify the fraction of Cr atoms on substitutional, interstitial, and random sites in epitaxial Ga1-x Crx N films grown by reactive molecular-beam epitaxy. The morphology of these films and correlation with their magnetic properties has been investigated. Films grown at temperatures below ~750 °C have up to 90% of Cr occupying substitutional sites. Post-growth annealing at 825 °C results in a systematic drop in the fraction of substitutional Cr as well as a fall off in the ferromagnetic signal. The roles of nonsubstitutional Cr in transferring charge from the Cr t2 band and segregation of substitutional Cr in the loss of magnetism are discussed. Overall, these results provide strong microscopic evidence that Cr-doped III-N systems are dilute magnetic semiconductors.

Original languageEnglish (US)
Article number012504
JournalApplied Physics Letters
Volume86
Issue number1
DOIs
StatePublished - Jan 2005

Fingerprint

substitutes
backscattering
interstitials
molecular beam epitaxy
magnetic properties
annealing
spectroscopy
atoms
temperature

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

The role of Cr substitution on the ferromagnetic properties of Ga 1-xCr xN. / Singh, Rakesh; Wu, Stephen Y.; Liu, H. X.; Gu, Lin; Smith, David; Newman, Nathan.

In: Applied Physics Letters, Vol. 86, No. 1, 012504, 01.2005.

Research output: Contribution to journalArticle

Singh, Rakesh ; Wu, Stephen Y. ; Liu, H. X. ; Gu, Lin ; Smith, David ; Newman, Nathan. / The role of Cr substitution on the ferromagnetic properties of Ga 1-xCr xN. In: Applied Physics Letters. 2005 ; Vol. 86, No. 1.
@article{0d9be4522b6d41908e7ca86f7e270ef5,
title = "The role of Cr substitution on the ferromagnetic properties of Ga 1-xCr xN",
abstract = "Angular-dependent channeling Rutherford backscattering spectroscopy (c-RBS) has been used to quantify the fraction of Cr atoms on substitutional, interstitial, and random sites in epitaxial Ga1-x Crx N films grown by reactive molecular-beam epitaxy. The morphology of these films and correlation with their magnetic properties has been investigated. Films grown at temperatures below ~750 °C have up to 90{\%} of Cr occupying substitutional sites. Post-growth annealing at 825 °C results in a systematic drop in the fraction of substitutional Cr as well as a fall off in the ferromagnetic signal. The roles of nonsubstitutional Cr in transferring charge from the Cr t2 band and segregation of substitutional Cr in the loss of magnetism are discussed. Overall, these results provide strong microscopic evidence that Cr-doped III-N systems are dilute magnetic semiconductors.",
author = "Rakesh Singh and Wu, {Stephen Y.} and Liu, {H. X.} and Lin Gu and David Smith and Nathan Newman",
year = "2005",
month = "1",
doi = "10.1063/1.1843276",
language = "English (US)",
volume = "86",
journal = "Applied Physics Letters",
issn = "0003-6951",
publisher = "American Institute of Physics Publising LLC",
number = "1",

}

TY - JOUR

T1 - The role of Cr substitution on the ferromagnetic properties of Ga 1-xCr xN

AU - Singh, Rakesh

AU - Wu, Stephen Y.

AU - Liu, H. X.

AU - Gu, Lin

AU - Smith, David

AU - Newman, Nathan

PY - 2005/1

Y1 - 2005/1

N2 - Angular-dependent channeling Rutherford backscattering spectroscopy (c-RBS) has been used to quantify the fraction of Cr atoms on substitutional, interstitial, and random sites in epitaxial Ga1-x Crx N films grown by reactive molecular-beam epitaxy. The morphology of these films and correlation with their magnetic properties has been investigated. Films grown at temperatures below ~750 °C have up to 90% of Cr occupying substitutional sites. Post-growth annealing at 825 °C results in a systematic drop in the fraction of substitutional Cr as well as a fall off in the ferromagnetic signal. The roles of nonsubstitutional Cr in transferring charge from the Cr t2 band and segregation of substitutional Cr in the loss of magnetism are discussed. Overall, these results provide strong microscopic evidence that Cr-doped III-N systems are dilute magnetic semiconductors.

AB - Angular-dependent channeling Rutherford backscattering spectroscopy (c-RBS) has been used to quantify the fraction of Cr atoms on substitutional, interstitial, and random sites in epitaxial Ga1-x Crx N films grown by reactive molecular-beam epitaxy. The morphology of these films and correlation with their magnetic properties has been investigated. Films grown at temperatures below ~750 °C have up to 90% of Cr occupying substitutional sites. Post-growth annealing at 825 °C results in a systematic drop in the fraction of substitutional Cr as well as a fall off in the ferromagnetic signal. The roles of nonsubstitutional Cr in transferring charge from the Cr t2 band and segregation of substitutional Cr in the loss of magnetism are discussed. Overall, these results provide strong microscopic evidence that Cr-doped III-N systems are dilute magnetic semiconductors.

UR - http://www.scopus.com/inward/record.url?scp=19744382705&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=19744382705&partnerID=8YFLogxK

U2 - 10.1063/1.1843276

DO - 10.1063/1.1843276

M3 - Article

AN - SCOPUS:19744382705

VL - 86

JO - Applied Physics Letters

JF - Applied Physics Letters

SN - 0003-6951

IS - 1

M1 - 012504

ER -