Roles of Orbitals in Transition Metal Oxides
Neutron and synchrotron x-ray scattering experiments with additional bulk measurements such as the magnetization, and resitivity under high magnetic field have been performed from single crystals of the colossal magneto resistance (CMR) manganese oxides of Lal−xSrxMn03. Systematic experimental investigations show decisively that the complicated phase diagram around x ≈ 0.12 has been comprehended as the first order phase transition from metal to insulator applying magnetic field driven by the orbital order. The ferromagnetic insulting phase is not originated by the Jahn Teller interaction but is by the electron correlation, since the crystal symmetry is pseudo cubic. The novel CMR mechanism is proposed based on the present experimental investigations.
KeywordsManganese Oxide Spin Dynamic Colossal Magneto Resistance Orbital Order Anomalous Scattering
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- Y.Endoh, K.Hirota, Y.Murakami, T.Fukuda, H.Kimura, H.Nojiri, K.Kaneko, S.Ishihara, S.Okamoto and S.Maekawa; unpublishedGoogle Scholar
- Y. Endoh, Magnetism In Metals, Matematisk-fysiske Meddeleleser,45, 149 (1997).Google Scholar
- V.E. Dmitrienko, Acta Cryst.,A 39,29 (1983); D.H. Templeton and L. K. Templeton, Acta Cryst., A 41, 133 (1985)Google Scholar
- V.E. Dmitrienko, Acta Cryst., A39,29 (1983); D.H. Templeton and L. K. Templeton, Acta Cryst., A41, 133 (1985)Google Scholar
- M. Blume,Resonant Anomalous x-ray Scattering –Theory and Applications-edited by G. Materik, C.J. Sparks and K. Fisher; Elsevier Science B.V. (1994)Google Scholar
- H. Nojiri, unpublishedGoogle Scholar
- S. Okamoto, unpublishedGoogle Scholar