Femtosecond Snapshot Holography with Extended Reference Using Extreme Ultraviolet Free-Electron Laser

Emerging free-electron lasers (FELs) at short wavelengths open a new possibility for ultrafast microscopy of transient phenomena at high spatial resolution due to the ultrashort pulse duration. As a first step, we performed sub-picosecond snapshot imaging with extreme ultraviolet FEL by adopting a recently proposed holographic technique, holography with extended reference by autocorrelation linear differential operation (HERALDO). We point out that HERALDO enables efficient single-shot phase-contrast imaging by carefully designing the aperture size of the reference without sacrificing spatial resolution. The successful reconstruction of a test pattern from a single-shot hologram demonstrates an effective method of taking phase-contrast sub-picosecond snapshots. (C) 2010 The Japan Society of Applied Physics