Research

SEM image of a Ficus cystolith

Optics of biogenic systems

Biogenic crystals are abundant in both the plant and animal kingdoms. Often, these can have an optical function. Together with the groups of Profs. Lia Addadi and Steve Weiner we have been studying some of these systems using a combination of structural and optical characterization tools.

Sub-diffraction limited image of emitters on a circle

Far-field sub-diffraction-limited imaging techniques

The problem of surpassing the diffraction barrier in far-field optical microscopy is of tremendous interest both from a fundamental point of view and from a practical one. We are exploring new schemes which would simplify current techniques for microscopy beyond the diffraction limit.

Schematic of a single core-shell semiconductor nanopletelet

Carrier dynamics in semiconductor quantum dots

Unlike many organic chromofores, semiconductor quantum dots can accomodate multiple excitations and thus exhibit unique nonlinear optical properties. We use optical spectroscopy tools to study phenomena such as luminescence upconversion, optical gain and the quantum confined Stark effect.

Lamella TEM image of a hybrid quantum dot-dye cell

Quantum dot enabled photovoltaic cells

We combine fundamental studies of the photophysics of semiconductor quantum dots adsorbed on surfaces with realizations of new designs for third-generation photovoltaic cells incorporating quantum dots.