Spin and lattice dynamics of La2/3Ca1/3MnO3 doped with 1% 119Sn

• Autorzy: Przewoźnik J. , Żukrowski J. , Chmist J. , Japa E. , Kołodziejczyk A. , Krop K. , Kellner K. , Gritzner G.
• Konferencja: Proceedings of the All-Polish Seminar on Mössbauer Spectroscopy OSSM'04
• Języki publikacji: EN

Abstrakty

EN

1 at.% 119Sn doped La0.67Ca0.33MnO3 compound was studied by Mössbauer spectroscopy, magnetization, AC susceptibility and resistivity measurements. Huge separation (66 K) of the transition temperatures from the ferromagnetic (FM) to paramagnetic (PM) state (TC) and from metallic to insulating state (TM-I) clearly shows that transition from FM metallic to PM insulator phase goes via FM insulator phase. The Mn lattice dynamics was studied by the relative changes of Lamb-Mössbauer factor f as a function of temperature. In the Debye approximation from the calculated ln(f/f0) values of the characteristic Debye temperatures (čD) were estimated for the FM (368(10) K) and PM (391(6) K) phases. No anomaly of -ln(f/f0) at TM-I and its rather spurious increase around TC was found. The 119Sn isotope as a local diamagnetic probe samples the transferred hyperfine field (Bhf) from its neighbour Mn magnetic moments and witnesses the dynamics of the Mn moments. Theoretical curve based on the molecular field theory was fitted to the experimental values of Bm hf ax and the value of the ordering temperature (TC * H 280 K) of Mn moments inside the large FM domains was estimated. It is much higher than the TC (172 K) obtained from magnetization measurement. The coexistence of FM and PM phases, which is evident from the shape of our 119Sn Mössbauer spectra, was confirmed for temperatures T e 150 K and indicates the inhomogeneous character of the magnetic transition.

Słowa kluczowe

EN

119Sn Mössbauer; LCMO manganites; f-factor; metal-insulator

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2004
• Tom: Vol. 49,suppl.3
• Strony: 37--42
• Opis fizyczny: Bibliogr. 14 poz., rys.

Twórcy

autor

Przewoźnik J.

• Department of Solid State Physics, Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, 30 A. Mickiewicza Ave., 30-059 Kraków, Poland, Tel.: [phone], Fax: [phone]

autor

Żukrowski J.

• Department of Solid State Physics, Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, 30 A. Mickiewicza Ave., 30-059 Kraków, Poland, Tel.: [phone], Fax: [phone]

autor

Chmist J.

• Department of Solid State Physics, Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, 30 A. Mickiewicza Ave., 30-059 Kraków, Poland, Tel.: [phone], Fax: [phone]

autor

Japa E.

• Department of Solid State Physics, Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, 30 A. Mickiewicza Ave., 30-059 Kraków, Poland, Tel.: [phone], Fax: [phone]

autor

Kołodziejczyk A.

• Department of Solid State Physics, Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, 30 A. Mickiewicza Ave., 30-059 Kraków, Poland, Tel.: [phone], Fax: [phone]

autor

Krop K.

• Department of Solid State Physics, Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, 30 A. Mickiewicza Ave., 30-059 Kraków, Poland, Tel.: [phone], Fax: [phone]

autor

Kellner K.

• Institut für Chemische Technologie Anorganischer Stoffe, J. Kepler Universität Linz, A-4040 Linz, Austria

autor

Gritzner G.

• Institut für Chemische Technologie Anorganischer Stoffe, J. Kepler Universität Linz, A-4040 Linz, Austria

Bibliografia

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