TY - JOUR
T1 - Optical investigations on Y2-xBixRu2O7
T2 - Electronic structure evolutions related to the metal-insulator transition
AU - Lee, J. S.
AU - Moon, S. J.
AU - Noh, T. W.
AU - Takeda, T.
AU - Kanno, R.
AU - Yoshii, S.
AU - Sato, M.
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2005/7/15
Y1 - 2005/7/15
N2 - Optical conductivity spectra of cubic pyrochlore Y2-xBixRu2O7 (0.0≤x≤2.0) compounds are investigated. As a metal-insulator transition (MIT) occurs around x=0.8, large spectral changes are observed. With increase of x, the correlation-induced peak between the lower and the upper Hubbard bands seems to be suppressed, and a strong mid-infrared feature is observed. In addition, the p-d charge transfer peak shifts to the lower energies. The spectral changes cannot be explained by electronic structural evolutions in the simple bandwidth-controlled MIT picture, but are consistent with those in the filling-controlled MIT picture. In addition, they are also similar to the spectral changes of Y2-xCaxRu2O7 compounds, which is a typical filling-controlled system. This work suggests that, near the MIT, the Ru bands could be doped with the easily polarizable Bi cations.
AB - Optical conductivity spectra of cubic pyrochlore Y2-xBixRu2O7 (0.0≤x≤2.0) compounds are investigated. As a metal-insulator transition (MIT) occurs around x=0.8, large spectral changes are observed. With increase of x, the correlation-induced peak between the lower and the upper Hubbard bands seems to be suppressed, and a strong mid-infrared feature is observed. In addition, the p-d charge transfer peak shifts to the lower energies. The spectral changes cannot be explained by electronic structural evolutions in the simple bandwidth-controlled MIT picture, but are consistent with those in the filling-controlled MIT picture. In addition, they are also similar to the spectral changes of Y2-xCaxRu2O7 compounds, which is a typical filling-controlled system. This work suggests that, near the MIT, the Ru bands could be doped with the easily polarizable Bi cations.
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U2 - 10.1103/PhysRevB.72.035124
DO - 10.1103/PhysRevB.72.035124
M3 - Article
AN - SCOPUS:33749233554
VL - 72
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
SN - 0163-1829
IS - 3
M1 - 035124
ER -