Raman scattering study of rare-earth hexaboride

N. Ogita, S. Nagai, M. Udagawa, F. Iga, M. Sera, T. Oguchi, Jun Akimitsu, S. Kunii

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

The excitation-energy, polarization, pressure, and temperature dependences of Raman scattering spectra have been measured for the RB6 crystals (R=Ca2+, La3+, Ce3+, Pr3+, Sm2.6+, Gd3+, Dy3+, and Yb2+). In the Raman spectra, the extra peaks have been clearly observed at around 200cm-1, except for the Raman-active phonons and CEF excitations. The extra peaks show anomalous behavior in the temperature, polarization, and lattice parameter dependences. These anomalous behaviors originate from the vibration of the rare-earth ions in octahedral B6 cage, and the extra peaks can be assigned as the second-order Raman excitations of T1u phonon at Brillouin zone boundary. In the results of pressure dependence, the valence of all Sm ions in SmB6 becomes trivalent above 20 GPa at room temperature.

Original languageEnglish
Pages (from-to)941-943
Number of pages3
JournalPhysica B: Condensed Matter
Volume359-361
Issue numberSPEC. ISS.
DOIs
Publication statusPublished - Apr 30 2005
Externally publishedYes

Fingerprint

Rare earths
Raman scattering
rare earth elements
Raman spectra
pressure dependence
Ions
Polarization
excitation
Excitation energy
polarization
Phonons
Brillouin zones
Temperature
Lattice constants
lattice parameters
ions
phonons
valence
vibration
temperature dependence

Keywords

  • Raman scattering
  • Rare-earth hexaboride
  • Valence change

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics

Cite this

Ogita, N., Nagai, S., Udagawa, M., Iga, F., Sera, M., Oguchi, T., ... Kunii, S. (2005). Raman scattering study of rare-earth hexaboride. Physica B: Condensed Matter, 359-361(SPEC. ISS.), 941-943. https://doi.org/10.1016/j.physb.2005.01.270

Raman scattering study of rare-earth hexaboride. / Ogita, N.; Nagai, S.; Udagawa, M.; Iga, F.; Sera, M.; Oguchi, T.; Akimitsu, Jun; Kunii, S.

In: Physica B: Condensed Matter, Vol. 359-361, No. SPEC. ISS., 30.04.2005, p. 941-943.

Research output: Contribution to journalArticle

Ogita, N, Nagai, S, Udagawa, M, Iga, F, Sera, M, Oguchi, T, Akimitsu, J & Kunii, S 2005, 'Raman scattering study of rare-earth hexaboride', Physica B: Condensed Matter, vol. 359-361, no. SPEC. ISS., pp. 941-943. https://doi.org/10.1016/j.physb.2005.01.270
Ogita N, Nagai S, Udagawa M, Iga F, Sera M, Oguchi T et al. Raman scattering study of rare-earth hexaboride. Physica B: Condensed Matter. 2005 Apr 30;359-361(SPEC. ISS.):941-943. https://doi.org/10.1016/j.physb.2005.01.270
Ogita, N. ; Nagai, S. ; Udagawa, M. ; Iga, F. ; Sera, M. ; Oguchi, T. ; Akimitsu, Jun ; Kunii, S. / Raman scattering study of rare-earth hexaboride. In: Physica B: Condensed Matter. 2005 ; Vol. 359-361, No. SPEC. ISS. pp. 941-943.
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