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Resonant photoemission spectroscopy study of insulator-to-metal transition in Cr- and Ru-doped Nd_{1/2}A_{1/2}Mn_{1-y} O_{3} (A=Ca, Sr)

J. -S. Kang·J. H. Kim·A. Sekiyama·S. Kasai·S. Suga·S. W. Han·K. H. Kim·E. J. Choi·T. Kimura·T. Muro·Y. Saitoh·C. G. Olson·J. H. Shim·B. I. Min
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Abstract

Electronic structures of very dilute Cr- or Ru-doped Nd_{1/2}A_{1/2}MnO_{3} (NAMO; A=Ca, Sr) manganites have been investigated using the Mn and Cr 2p -> 3d resonant photoemission spectroscopy (PES). All the Cr- and Ru-doped NAMO systems exhibit the clear metallic Fermi edges in the Mn e_g spectra near E_F, consistent with their metallic ground states. The Cr 3d states with t^3_{2g} configuration are at ~ 1.3 eV below E_F, and the Cr e_{g} states do not participate in the formation of the band near E_F. Cr- and Ru-induced ferromagnetism and insulator-to-metal transitions can be understood with their measured electronic structures.

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J. -S. Kang, J. H. Kim, A. Sekiyama, S. Kasai, S. Suga, S. W. Han, K. H. Kim, E. J. Choi, T. Kimura, T. Muro, Y. Saitoh, C. G. Olson, J. H. Shim, B. I. Min. 2002-11-03. Resonant photoemission spectroscopy study of insulator-to-metal transition in Cr- and Ru-doped Nd_{1/2}A_{1/2}Mn_{1-y} O_{3} (A=Ca, Sr). https://doi.org/10.1103/physrevb.68.012410

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