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Title: Localized Excitation in the Hybridization Gap in YbAl{sub 3}

Abstract

The intermediate valence compound YbAl{sub 3} exhibits a broad magnetic excitation in the inelastic neutron scattering spectrum with characteristic energy E{sub 1}{approx_equal}50 meV, equal to the Kondo energy (T{sub K}{approx}600-700 K). In the low temperature (T<T{sub coh}{approx}40 K) Fermi liquid state, however, a new peak in the scattering occurs at E{sub 2}{approx_equal}33 meV, which lies in the hybridization gap that exists in this compound. We report inelastic neutron scattering results for a single-crystal sample. The scattering at energies near E{sub 1} qualitatively has the momentum (Q) dependence expected for interband scattering across the indirect gap. The scattering near E{sub 2} has a very different Q dependence: it is a weak function of Q over a large fraction of the Brillouin zone and is smallest near (1/2,1/2,1/2). A possibility is that the peak at E{sub 2} arises from a spatially localized excitation in the hybridization gap.

Authors:
;  [1];  [2];  [1];  [3];  [4];  [3]; ; ;  [5];  [6];  [7]
  1. University of California, Irvine, California 92697 (United States)
  2. (United States)
  3. Argonne National Laboratory, Argonne, Illinois 60439 (United States)
  4. (United Kingdom)
  5. Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
  6. ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX (United Kingdom)
  7. Ames Laboratory, Iowa State University, Ames, Iowa 50011 (United States)
Publication Date:
OSTI Identifier:
20778837
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevLett.96.117206; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM ALLOYS; BINARY ALLOY SYSTEMS; BRILLOUIN ZONES; EXCITATION; FERMI GAS; HYBRIDIZATION; INELASTIC SCATTERING; KONDO EFFECT; MONOCRYSTALS; NEUTRON DIFFRACTION; SPECTRA; VALENCE; YTTERBIUM ALLOYS

Citation Formats

Christianson, A.D., Fanelli, V.R., Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Lawrence, J.M., Goremychkin, E.A., ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX, Osborn, R., Bauer, E.D., Sarrao, J.L., Thompson, J.D., Frost, C.D., and Zarestky, J. L. Localized Excitation in the Hybridization Gap in YbAl{sub 3}. United States: N. p., 2006. Web. doi:10.1103/PHYSREVLETT.96.1.
Christianson, A.D., Fanelli, V.R., Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Lawrence, J.M., Goremychkin, E.A., ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX, Osborn, R., Bauer, E.D., Sarrao, J.L., Thompson, J.D., Frost, C.D., & Zarestky, J. L. Localized Excitation in the Hybridization Gap in YbAl{sub 3}. United States. doi:10.1103/PHYSREVLETT.96.1.
Christianson, A.D., Fanelli, V.R., Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Lawrence, J.M., Goremychkin, E.A., ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX, Osborn, R., Bauer, E.D., Sarrao, J.L., Thompson, J.D., Frost, C.D., and Zarestky, J. L. Fri . "Localized Excitation in the Hybridization Gap in YbAl{sub 3}". United States. doi:10.1103/PHYSREVLETT.96.1.
@article{osti_20778837,
title = {Localized Excitation in the Hybridization Gap in YbAl{sub 3}},
author = {Christianson, A.D. and Fanelli, V.R. and Los Alamos National Laboratory, Los Alamos, New Mexico 87545 and Lawrence, J.M. and Goremychkin, E.A. and ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX and Osborn, R. and Bauer, E.D. and Sarrao, J.L. and Thompson, J.D. and Frost, C.D. and Zarestky, J. L.},
abstractNote = {The intermediate valence compound YbAl{sub 3} exhibits a broad magnetic excitation in the inelastic neutron scattering spectrum with characteristic energy E{sub 1}{approx_equal}50 meV, equal to the Kondo energy (T{sub K}{approx}600-700 K). In the low temperature (T<T{sub coh}{approx}40 K) Fermi liquid state, however, a new peak in the scattering occurs at E{sub 2}{approx_equal}33 meV, which lies in the hybridization gap that exists in this compound. We report inelastic neutron scattering results for a single-crystal sample. The scattering at energies near E{sub 1} qualitatively has the momentum (Q) dependence expected for interband scattering across the indirect gap. The scattering near E{sub 2} has a very different Q dependence: it is a weak function of Q over a large fraction of the Brillouin zone and is smallest near (1/2,1/2,1/2). A possibility is that the peak at E{sub 2} arises from a spatially localized excitation in the hybridization gap.},
doi = {10.1103/PHYSREVLETT.96.1},
journal = {Physical Review Letters},
number = 11,
volume = 96,
place = {United States},
year = {Fri Mar 24 00:00:00 EST 2006},
month = {Fri Mar 24 00:00:00 EST 2006}
}
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