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arXiv · 1103.1204

Ultrafast Spectral Weight Transfer in RBaCo2O6-delta (R=Sm, Gd, and Tb): A Role of Electronic Correlation in Photoinduced Phase Transition

Y. Okimoto·T. Miyata·M. S. Endo·M. Kurashima·K. Onda·T. Ishikawa·S. Koshihara·M. Lorenc·E. Collet·H. Cailleau·T. Arima
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Abstract

We performed femtosecond reflection spectroscopy on a series of perovskite-type cobalt oxide $R$BaCo$_2$O$_{6-δ}$ ($R$=Sm, Gd, and Tb) crystals, in which the electronic transfer was controlled by $R$. The transient reflectivity and the optical conductivity ($σ^{\rm PI}(ω)$) obtained by Kramers-Kronig analysis showed an ultrafast change within a time resolution ($\approx 150$ fs) at room temperature and the appearance of signals of a hidden state different from the high temperature metallic state. The transferred spectral weight in $σ^{\rm PI}(ω)$ upon photoexcitation sensitively depended on the $R$-species, indicating an important role of electronic correlation in the photoexcited state.

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Y. Okimoto, T. Miyata, M. S. Endo, M. Kurashima, K. Onda, T. Ishikawa, S. Koshihara, M. Lorenc, E. Collet, H. Cailleau, T. Arima. 2011-03-07. Ultrafast Spectral Weight Transfer in RBaCo2O6-delta (R=Sm, Gd, and Tb): A Role of Electronic Correlation in Photoinduced Phase Transition. https://arxiv.org/abs/1103.1204

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