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A Scaling Behavior of Spectral Weight Changes in Perovskite Manganites La_{0.7-y}Pr_{y}Ca_{0.3}MnO_3

K. H. Kim·J. H. Jung·D. J. Eom·T. W. Noh·Jaejun Yu·E. J. Choi
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Abstract

Optical conductivity spectra of La_{0.7-y}Pr_{y}Ca_{0.3}MnO_3 were systematically investigated. For metallic samples, the spectral weight below 0.5 eV, whose magnitude can be represented by the effective carrier number N_{eff}(0.5 eV), increases as temperature becomes lower. Regardless of the Pr doping, all the measured values of N_{eff}(0.5 eV)/T_C fall into one scaling curve. This scaling behavior could be explained by the theoretical model by Roeder et al. [Phys. Rev. Lett. 76, 1356 (1996)], which includes spin double exchange and Jahn-Teller lattice coupling to holes. With the Pr doping, far-infrared conductivities were found to be suppressed, probably due to the Anderson localization.

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K. H. Kim, J. H. Jung, D. J. Eom, T. W. Noh, Jaejun Yu, E. J. Choi. 1998-04-27. A Scaling Behavior of Spectral Weight Changes in Perovskite Manganites La_{0.7-y}Pr_{y}Ca_{0.3}MnO_3. https://doi.org/10.1103/physrevlett.81.4983

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