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Optical Evidence of Multiphase Coexistence in Single Crystalline (La,Pr,Ca)MnO3

H. J. Lee·K. H. Kim·M. W. Kim·T. W. Noh·B. G. Kim·T. Y. Koo·S. -W. Cheong·Y. J. Wang·X. Wei
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Abstract

We investigated temperature (T)- and magnetic field-dependent optical conductivity spectra (\s\w) of a La_5/8-yPr_yCa_3/8MnO_3 (y~0.35) single crystal, showing intriguing phase coexistence at low T. At T_C < T < T_CO, a dominant charge-ordered phase produces a large optical gap energy of ~0.4 eV. At T < T_C, at least two absorption bands newly emerge below 0.4 eV. Analyses of (\s\w) indicate that the new bands should be attributed to a ferromagnetic metallic and a charge-disordered phase that coexist with the charge-ordered phase. This optical study clearly shows that La_5/8-yPrCa_3/8MnO_3 (y~0.35) is composed of multiphases that might have different lattice strains.

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H. J. Lee, K. H. Kim, M. W. Kim, T. W. Noh, B. G. Kim, T. Y. Koo, S. -W. Cheong, Y. J. Wang, X. Wei. 2002-03-05. Optical Evidence of Multiphase Coexistence in Single Crystalline (La,Pr,Ca)MnO3. https://doi.org/10.1103/physrevb.65.115118

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