Condensed matter physics is one of the most exciting fields in physics. At the fundamental level, it serves as a foundation of many new discoveries in modern science. Over the past 50 years, 22 Nobel Prizes in Physics and 5 Nobel Prizes in Chemistry have been awarded to condensed matter physics and related areas. Condensed matter physics is also a foundation of many important modern technologies, such as energy, information, defense, and manufacturing.
Our major research goal is to understand ultrafast electron dynamics and their interactions with light on nanometer scales by developing unique experimental techniques with high temporal and spatial resolution. We use ultrafast lasers to manipulate, control, and detect electrons in nanomaterials, in order to understand energy relaxation, real space transport, spin dynamics, and radiative recombination of excited electrons. The materials studied include traditional three-dimensional bulk crystals of silicon, germanium, gallium arsenide; traditional two-dimensional quantum-well structures; new two-dimensional atomically-thin films of graphene, molybdenum disulfide, gallium selenide; and one-dimensional carbon nanotubes and gallium arsenide nanowires.
Our recent research topics include nanoscale ballistic electron transport in semiconductors, observation of the intrinsic inverse spin Hall effect, nonlinear optical effects of charge and spin currents, and electronic dynamics in graphene and topological insulators.