Photoinduced Phase Transition in $Pr_{0.5}Ca_{0.5}CoO_3$ Studied by Sequential Pulse Excitations

A perovskite-type cobalt oxide, $Pr_{0.5}Ca_{0.5}CoO_3$ (PCCO), shows photoinduced phase transition. In this study, we successively irradiated two laser pulses with different intensities to PCCO and probed the transient change of the reflection at 2.0 eV. Assuming propagation of the two different photoinduced metallic states, we could reproduce the time profiles as well as the magnitude in the reflectance change, indicating the fabrication of the photoinduced multilayered thin film in $Pr_{0.5}Ca_{0.5}CoO_3$.