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Ultrafast Photoinduced Formation of Metallic State in a Perovskite-type Manganite with Short Range Charge and Orbital Order

Yoichi Okimoto·Hiroyuki Matsuzaki·Yasuhide Tomioka·Istvan Kezsmarki·Takeshi Ogasawara·Masakazu Matsubara·Hiroshi Okamoto·Yoshinori Tokura
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Abstract

Femtosecond reflection spectroscopy was performed on a perovskite-type manganite, Gd0.55Sr0.45MnO3, with the short-range charge and orbital order (CO/OO). Immediately after the photoirradiation, a large increase of the reflectivity was detected in the mid-infrared region. The optical conductivity spectrum under photoirradiation obtained from the Kramers-Kronig analyses of the reflectivity changes demonstrates a formation of a metallic state. This suggests that ferromagnetic spin arrangements occur within the time resolution (ca. 200 fs) through the double exchange interaction, resulting in an ultrafast CO/OO to FM switching.

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Yoichi Okimoto, Hiroyuki Matsuzaki, Yasuhide Tomioka, Istvan Kezsmarki, Takeshi Ogasawara, Masakazu Matsubara, Hiroshi Okamoto, Yoshinori Tokura. 2007-02-05. Ultrafast Photoinduced Formation of Metallic State in a Perovskite-type Manganite with Short Range Charge and Orbital Order. https://doi.org/10.1143/jpsj.76.043702

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