Welcome to our Lab

Studies of light-matter interactions in quantum-confined systems have provided great insight into diverse and fundamental problems such as many-body interactions and entanglement. In particular, ultrafast optical spectroscopy has proved to be a powerful tool for elucidating electronic dynamics and coupling owing to its ability to access information that is difficult or impossible to obtain otherwise. Excitation with ultrashort pulses typically results in the creation of coherent superpositions and correlated many-particle states. Time evolution of such a system far from equilibrium can then be analyzed or even controlled in real time by subsequent pulses. The knowledge obtained from ultrafast optical spectroscopic studies complement those obtained from other techniques and provide a more accurate picture of system dynamics.

 

A variety of advanced nonlinear optical spectroscopy tools are employed in Dr. Li’s laboratory including four-wave-mixing (FWM) and two dimensional (2D) Fourier transform spectroscopy. (For introduction to these techniques, please click here.) 2D spectroscopy is an extension of the standard FWM technique, where the polarization phase evolution in two independent time periods is monitored. Correlation between absorption and emission frequencies is then established. Coupling between vibrational, rotational, and electronic resonances and how such coupling changes on a femtosecond time scale can be elucidated even in the presence of congested spectra.

 

Dr. Li’s research program focuses on the studies of quantum dynamics in various materials and nanostructures. Such research effort is relevant for applications in opto-electronics, quantum electronic and quantum computing.