Nonequilibrium Dynamics in Colloidal Semiconductor Nanomaterials

Structure, surface chemistry, and energetic disorder can dramatically affect excited state dynamics in low-dimensional systems. Using a combination of ultrafast laser spectroscopy, time-resolved optical microscopy, and kinetic modeling, I will show how these effects manifest in assemblies of colloidal quantum dots (QD) and atomically thin 2D semiconductors, which are promising components of next-generation photovoltaic and lighting technologies. In particular, I will demonstrate the counterintuitive role of entropy in the nonequilibrium population dynamics of excitons and charge carriers in nanoscale systems.

Speaker: William Tisdale, MIT