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Title: Incipient Orbital Order in Half-Metallic Ba{sub 2}FeReO{sub 6}

Abstract

Largely unquenched Re 5d orbital magnetic moments in half-metallic Ba{sub 2}FeReO{sub 6} drive a symmetry lowering transition from a cubic paramagnet to a compressed tetragonal (c/a<1) ferrimagnet below T{sub C}{approx}305 K, with a giant linear magnetoelastic constant and the spins lying spontaneously along the unique tetragonal axis. The large orbital magnetization and degree of structural deformation indicate proximity to a metal-insulator transition. These results point to an incipient orbitally ordered state in the metallic ferrimagnetic phase.

Authors:
;  [1];  [2];  [3];  [4];  [4];  [5];  [1];  [6];  [7];  [8]
  1. Instituto de Fisica 'Gleb Wataghin', UNICAMP, C.P. 6165, 13083-970, Campinas, Sao Paulo (Brazil)
  2. (Brazil)
  3. European Synchrotron Radiation Facility, F-38043, Grenoble (France)
  4. NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)
  5. (United States)
  6. Center for Superconductivity Research, University of Maryland, College Park, Maryland 20742 (United States)
  7. (India)
  8. Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 (India)
Publication Date:
OSTI Identifier:
20861587
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevLett.98.017204; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BARIUM COMPOUNDS; DEFORMATION; IRON COMPOUNDS; MAGNETIC MOMENTS; MAGNETIZATION; RHENIUM OXIDES; SPIN; SYMMETRY

Citation Formats

Azimonte, C., Granado, E., Laboratorio Nacional de Luz Sincrotron, C.P. 6192, 13084-971, Campinas, Sao Paulo, Cezar, J. C., Huang, Q., Lynn, J. W., Center for Superconductivity Research, University of Maryland, College Park, Maryland 20742, Campoy, J. C. P., Gopalakrishnan, J., Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, and Ramesha, K. Incipient Orbital Order in Half-Metallic Ba{sub 2}FeReO{sub 6}. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.017204.
Azimonte, C., Granado, E., Laboratorio Nacional de Luz Sincrotron, C.P. 6192, 13084-971, Campinas, Sao Paulo, Cezar, J. C., Huang, Q., Lynn, J. W., Center for Superconductivity Research, University of Maryland, College Park, Maryland 20742, Campoy, J. C. P., Gopalakrishnan, J., Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, & Ramesha, K. Incipient Orbital Order in Half-Metallic Ba{sub 2}FeReO{sub 6}. United States. doi:10.1103/PHYSREVLETT.98.017204.
Azimonte, C., Granado, E., Laboratorio Nacional de Luz Sincrotron, C.P. 6192, 13084-971, Campinas, Sao Paulo, Cezar, J. C., Huang, Q., Lynn, J. W., Center for Superconductivity Research, University of Maryland, College Park, Maryland 20742, Campoy, J. C. P., Gopalakrishnan, J., Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, and Ramesha, K. Fri . "Incipient Orbital Order in Half-Metallic Ba{sub 2}FeReO{sub 6}". United States. doi:10.1103/PHYSREVLETT.98.017204.
@article{osti_20861587,
title = {Incipient Orbital Order in Half-Metallic Ba{sub 2}FeReO{sub 6}},
author = {Azimonte, C. and Granado, E. and Laboratorio Nacional de Luz Sincrotron, C.P. 6192, 13084-971, Campinas, Sao Paulo and Cezar, J. C. and Huang, Q. and Lynn, J. W. and Center for Superconductivity Research, University of Maryland, College Park, Maryland 20742 and Campoy, J. C. P. and Gopalakrishnan, J. and Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 and Ramesha, K.},
abstractNote = {Largely unquenched Re 5d orbital magnetic moments in half-metallic Ba{sub 2}FeReO{sub 6} drive a symmetry lowering transition from a cubic paramagnet to a compressed tetragonal (c/a<1) ferrimagnet below T{sub C}{approx}305 K, with a giant linear magnetoelastic constant and the spins lying spontaneously along the unique tetragonal axis. The large orbital magnetization and degree of structural deformation indicate proximity to a metal-insulator transition. These results point to an incipient orbitally ordered state in the metallic ferrimagnetic phase.},
doi = {10.1103/PHYSREVLETT.98.017204},
journal = {Physical Review Letters},
number = 1,
volume = 98,
place = {United States},
year = {Fri Jan 05 00:00:00 EST 2007},
month = {Fri Jan 05 00:00:00 EST 2007}
}
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