By The Center for Nanoscale Materials
The UEM’s application is for investigating ultrafast (sub-picosecond) structural and chemical dynamics in materials at the nanoscale using electrons. The instrument is based on a JEOL JEM2100PLUS electron microscope and Altos Photonics lasers and has the following features: (a) a tunable femtosecond laser with a high repetition rate, (b) multiple routes to produce a pulsed electron beam, (c) a synchronous laser-pumped, pulsed transmission electron microscope that is outfitted with high-sensitivity cameras and electron energy filtering. This tool opens the door to an area of scientific understanding not available with any standard electron microscope, namely, the understanding of fast (sub-picosecond to nanosecond) dynamics and short-lived metastable phases in materials with sub-nanometer spatial resolution. This key analytical tool can deliver insights on ultrafast structural and chemical changes to a wide range of systems. The technical specifications are: Temporal resolution: approximately 1 ps Spatial resolution: approximately 1 nm Energy resolution: approximately 1 eV Pump laser wavelengths: 515 nm, 325-450 nm, 650-900 nm, 1030 nm, and 1200-2000 nm Repetition rate: 10-500 kHz (fs laser), 1-100 kHz (ns laser) Scientific Contact: Haihua Liu and Thomas Gage
