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Temperature-dependent optical reflectivity spectra were measured on cleaved surfaces of La 0.825 Sr 0.175 MnO 3 single crystals up to 6.6 eV. The present result demonstrates that the exchange-gap excitation in the optical conductivity spectrum splits into two parts (ϳ3.2 and ϳ5 eV͒. This indicates that the t 2g orbitals also participate in the reconstruction of the optical excitation caused by spin polarization. Based on the present result, we propose and discuss a model for the electronic structure of this prototypical double-exchange material. We also discuss the charge dynamics of the conducting carriers in terms of being a bad metal.

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