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Optical spectra measured on cleaved surfaces of double-exchange ferromagnet La1-xSrxMnO3

K. Takenaka·K. Iida·Y. Sawaki·S. Sugai·Y. Moritomo·A. Nakamura
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Abstract

Optical reflectivity spectra were measured on cleaved surfaces of La1-xSrxMnO3 single crystals (x=0.175, T_C=283 K) over a temperature range 10-295 K. The optical conductivity $sigma(ω)$ shows, keeping single-component nature, incoherent-to-coherent crossover with increase of electrical conductivity. The $σ(ω)$ spectrum of low-temperature ferromagnetic-metallic phase (10 K) exhibits a pronounced Drude-like component with large spectral weight, contrary to the previous result. The present result indicates that the optical spectrum of the manganites is sensitive to condition of sample surfaces.

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K. Takenaka, K. Iida, Y. Sawaki, S. Sugai, Y. Moritomo, A. Nakamura. 1999-05-21. Optical spectra measured on cleaved surfaces of double-exchange ferromagnet La1-xSrxMnO3. https://doi.org/10.1002/(sici)1521-3951(199909)215%3A1%3C637%3A%3Aaid-pssb637%3E3.0.co%3B2-4

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