Femtosecond Coherent Imaging

Observation of ultrafast phenomena in atomic- or nano-scale requires ultrafast camera. When an object is illuminated by flash light in a time scale shorter than the object movement time, snap shot images can be recorded without blurring. The flash duration of synchrotron radiation is typically a few ten pico-second, and was not enough fast to observe ultrafast phenomena in atomic- or nano-scale. X-ray free-electron laser realizes much shorter flash duration in femtosecond scale.

X-rays has much shorter wavelengths than visible light, and thus enables us to observe much smaller objects such as atoms. Furthermore, x-rays would enables us to observe much faster phenomena than visible light, when x-rays with ultimately short flash duration become available. Together it means that x-rays has great potential to record atomic movie. A time series of coherent x-ray diffraction patterns will unvail structural dynamics deep inside the sample.

     Fig.　Schematic of Femtosecond Coherent Imaging Using X-ray Free-Electron Laser

1. Femtosecond Snapshot Holography with Extended Reference Using Extreme Ultraviolet Free-Electron Laser
   Yoshinori Nishino, Yoshihito Tanaka, Makoto Okada, Motohiro Okaya, Yoshihito Uozaki, Kimihiko Nozaki, Makina Yabashi, Mitsuru Nagasono, Kensuke Tono, Hiroaki Kimura, Haruhiko Ohashi, Shinji Matsui, Tetsuya Ishikawa, and Eiichiro Matsubara
   Applied Physics Express 3 (2010) 102701.