Femtosecond low-energy electron diffraction and imaging

We present an experimental approach for the investigation of ultrafast structural dynamics in low-dimensional systems like two-dimensional materials, surfaces, and nanostructures. Time-resolved diffraction technique with low-energy electrons in the sub-kV range provides femtosecond temporal resolution and high surface sensitivity. Besides an operation mode for femtosecond low-energy electron diffraction (fs-LEED), the instrument also provides femtosecond point projection imaging (fs-PPI), which allows for mapping of transient electric fields and ultrafast currents in photoexcited nanostructures