- Tytuł:
- Investigation of Mixed Valence State of $Sm_{1-x}B_{6}$ and $Sm_{1-x}La_{x}B_{6}$ by XANES
- Autorzy:
-
Gabáni, S.
Flachbart, K.
Bednarčík, J.
Welter, E.
Filipov, V.
Shitsevalova, N. - Powiązania:
- https://bibliotekanauki.pl/articles/1371509.pdf
- Data publikacji:
- 2014-07
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
78.70.Dm
71.28.+d
71.27.+a - Opis:
- We investigated the valence states of samarium ions in Sm deficient $Sm_{1-x}B_{6}$ (x=0.03, 0.05, 0.08, 0.1 and 0.2) sintered samples, in single crystalline solid solutions $Sm_{1-x}La_{x}B_{6}$ (x=0.16, 0.28, 0.4, 0.55 and 0.7) as well as in a $SmB_{6}$ single crystal by X-ray absorption near edge structure (XANES) between 4.2 and 300 K. It was shown that the mixed valence state $v_{Sm}$ of Sm-ions ($v_{Sm}$ ≈ 2.51 for $SmB_{6}$ at 4.2 K) in deficient samples is changed but maintained up to a concentration of 20% of vacancies and up to a concentration of 70% in samples doped with trivalent La-ions, and that in both cases it increases with temperature. On the other hand, the value of $v_{Sm}$ increases with increasing vacancy level, whereas it decreases with increasing $La^{3+}$ substitution. The obtained dependences of Sm-valence in $SmB_{6}$ on vacancy as well as on $La^{3+}$ ion concentration are in good agreement with susceptibility measurements and exact numerical calculation of the spinless Falicov-Kimball model in two dimensions.
- Źródło:
-
Acta Physica Polonica A; 2014, 126, 1; 338-339
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki