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 language | English |
|---|---|
| Pages (from-to) | 941-943 |
| Number of pages | 3 |
| Journal | Physica B: Condensed Matter |
| Volume | 359-361 |
| Issue number | SPEC. ISS. |
| DOIs | |
| Publication status | Published - Apr 30 2005 |
| Externally published | Yes |
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Keywords
- Raman scattering
- Rare-earth hexaboride
- Valence change
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
Cite this
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 journal › Article
}
TY - JOUR
T1 - Raman scattering study of rare-earth hexaboride
AU - Ogita, N.
AU - Nagai, S.
AU - Udagawa, M.
AU - Iga, F.
AU - Sera, M.
AU - Oguchi, T.
AU - Akimitsu, Jun
AU - Kunii, S.
PY - 2005/4/30
Y1 - 2005/4/30
N2 - 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.
AB - 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.
KW - Raman scattering
KW - Rare-earth hexaboride
KW - Valence change
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UR - http://www.scopus.com/inward/citedby.url?scp=18244377142&partnerID=8YFLogxK
U2 - 10.1016/j.physb.2005.01.270
DO - 10.1016/j.physb.2005.01.270
M3 - Article
AN - SCOPUS:18244377142
VL - 359-361
SP - 941
EP - 943
JO - Physica B: Condensed Matter
JF - Physica B: Condensed Matter
SN - 0921-4526
IS - SPEC. ISS.
ER -