Giant Magneto-Resistance in Nd0.7Sr0.3MnO3 at Optical Frequencies
نویسندگان
چکیده
The optical properties of Nd0.7Sr0.3MnO3 thin films have been studied from 5 meV to 25 meV and from 0.25 eV to 3 eV, at temperatures from 15 K to 300 K and magnetic fields up to 8.9 T. A large transfer of spectral weight from high energy to low energy occurs as the temperature is decreased below 180 K, where the dc resistivity peaks, or as the magnetic field is increased. The optical data are found to be consistent with models that include both the double exchange interaction and the dynamic Jahn-Teller effect on the Mn3+ eg levels. PACS 75.70.P, 78.20.L, 78.3 Typeset using REVTEX
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