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Transient differential reflectivity of ferromagnetic and paramagnetic phases in the bilayered manganite La1.24Sr1.76Mn2O7

Y. Hirobe·Y. Kubo·K. Kouyama·H. Kunugita·K. Ema·H. Kuwahara
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Abstract

Photoinduced effects in a single crystal of bilayered manganites, La2-2xSr1+2xMn2O7 (x=0.38), were investigated in a wide range of temperatures by pump-probe measurement at a photon energy of 1.6eV. In a ferromagnetic metallic state, significant enhancement of positive rise in differential reflectivity with a slow relaxing time of hundred picoseconds was observed just below Tc=127K, indicating that the reflectivity change with the slow relaxation time constant is induced by laser heating. We have also observed an unconventional fast relaxing component that has a time constant of the order of ten picoseconds. This fast relaxing component, whose absolute value has an asymmetric peak at Tc, is presumably due to short-range correlation of Jahn-Teller distortion.

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Y. Hirobe, Y. Kubo, K. Kouyama, H. Kunugita, K. Ema, H. Kuwahara. 2004-12-06. Transient differential reflectivity of ferromagnetic and paramagnetic phases in the bilayered manganite La1.24Sr1.76Mn2O7. https://doi.org/10.1016/j.ssc.2004.12.012

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