Ultrafast Microscopy

Understanding of the carrier dynamics under quantum confinement is a key to advancing nanoscale science and technology. Although scanning probe techniques can investigate dynamics of individual nanostructures, there is also a clear need for ultrafast imaging microscopic techniques for studies of dynamics in complex nanostructures comprising of electronic, optical, or biological elements. We have developed the interferometric time-resolved photoemission electron microscopy (ITR-PEEM) technique by combining time resolved photoemission with photoemission electron microscopy. The ITR-PEEM technique enables us to record movies of ultrafast electric field and electron dynamics with <10 nm spatial resolution and 330 attosecond pump-probe time interval per frame. With ITR-PEEM we study surface plasmon dynamics in nanostructured metal films.  You can see an attosecond movie of plasmonic modes in a silver nanocrystal below.

Our studies on ultrafast microscopy of plasmonic nanostructures is performed in collaboration with the NSF Center for Chemistry at the Space-Time Limit (CaSTL). Recent measurements on ultrafast microscopy using our new LEEM/PEEM instrument were published in ACS Photonics.