Electronic Raman scattering and photoluminescence from La0.7Sr0.3MnO3 exhibiting giant magnetoresistance
نویسندگان
چکیده
Raman and Photoluminescence (PL) experiments on correlated metallic La0.7Sr0.3MnO3 have been carried out using different excitation wavelengths as a function of temperature from 15 K to 300 K. Our data suggest a Raman mode centered at 1800 cm and a PL band at 2.2 eV. The intensities of the two peaks decrease with increasing temperature. The Raman mode can be attributed to a plasmon excitation whose frequency and linewidths are consistent with the measured resistivities. The PL involves intersite electronic transitions of the manganese ions. PACS numbers: 78.30Hv, 71.27+a, 78.55Hx, 71.45Gm Typeset using REVTEX
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