Speaker
Description
Ultrafast electron microscopy enables the investigation of electron–photon interactions with femtosecond temporal and nanometer spatial resolution. We have developed a laser-integrated SEM for PINEM and ponderomotive electron–light interaction experiments. Electrons are initially generated by laser-triggered emission from a Schottky field emitter. Downstream, the electrons can interact with another laser pulse in the SEM sample chamber with flexible options for beam focusing and sample choice. Both laser pulses are characterized outside of the SEM using a custom-built FROG/autocorrelator. The chamber beam geometry is characterized with in-situ knife-edge measurements. Spatiotemporal overlap of the electron and optical pulses is established using laser-induced plasma focusing of the electrons as they pass near a gold foil. Electrons are detected post-interaction in a home-built electron spectrometer with sub-eV energy resolution. We present results from the commissioning of this new device.