- Tytuł:
- NMR ($\text{}^{55}$Mn, $\text{}^{139}$La) and Mössbauer Spectroscopy ($\text{}^{119}$Sn) Studies of (La$\text{}_{0.67}$Ca$\text{}_{0.33}$)(Mn$\text{}_{1-x}$Sn$\text{}_{x}$)O$\text{}_{3-δ}$ Compounds
- Autorzy:
- Przewoźnik, J.
- Powiązania:
- https://bibliotekanauki.pl/articles/2047327.pdf
- Data publikacji:
- 2007-05
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
76.60.-k
76.80.+y
75.47.Lx
77.80.Bh
75.47.Gk - Opis:
- A $\text{}^{119}$Sn Mössbauer spectroscopy and zero field $\text{}^{55}$Mn and $\text{}^{139}$La NMR studies of (La$\text{}_{0.67}$Ca$\text{}_{0.33}$)(Mn$\text{}_{1-x}$Sn$\text{}_{x}$)O$\text{}_{3-δ}$ (x=0, 0.01, 0.03, andδ≈0.06) were reported. The temperature evolution of the Sn hyperfine field (B$\text{}_{hf}$) for x=0.03 determined from the Mössbauer spectroscopy measurements was analysed within a molecular field model. A fit to the temperature dependence of B$\text{}_{hf}^{max}$ provided the Curie temperature T$\text{}_{C}^{*}$=160(3) K, which is in good agreement with T$\text{}_{C}$ obtained from dc magnetisation measurements. The $\text{}^{55}$Mn NMR spectra for $x=0$ and 0.01 show a single double exchange Mn$\text{}^{3+}\text{}^{/}\text{}^{4+}$ resonance line and exhibit strong Suhl-Nakamura relaxation effects characteristic of the ferromagnetic metallic phase. The spectra for x=0.03 show a coexistence of the double exchange line with the lines characteristic of Mn$\text{}^{3+}$ and Mn$\text{}^{4+}$ valence states. This shows that a 3% Sn doping strongly suppresses the double exchange interaction and leads to microscopic phase segregation into ferromagnetic metal and ferromagnetic insulator.
- Źródło:
-
Acta Physica Polonica A; 2007, 111, 5; 649-659
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł