At the Laboratories for Hybrid Optoelectronics we conduct research on the nanoscale -typically a few billionths of a meter or ~50000 times thinner than a human hair. At this scale the dominance of the quantum nature of matter is clearly evidenced in the physical properties of the systems we investigate. In our group we are particularly interested in the ways that light interacts with matter at this small scale and in the transient dynamics of these interactions which usually evolve in a few trillionths of a second.



 



 

Hybrid Nanostructures

Innovative hybrid systems are inspired by naturally-occurring biological-nanostructures that use energy transfer and recycling to transform light into chemical energy. Here we explore alternative ways of removing carriers from efficient light absorbing materials such as organic semiconductors and nanocrystal quantum dots (QDs) and transferring them into single crystal inorganic semiconductors with high carrier mobility. Such phenomena are yet to be observed and will pave the way for a completely new generation of hybrid optoelectronic devices. Using ultrafast spectroscopic techniques we investigate alternative ways of removing carriers from efficient light absorbing materials of low carrier mobility, such as organic semiconductors and nanocrystal quantum dots, and transferring them into single crystal inorganic semiconductors with high carrier mobility. We recently demonstrated record exciton transfer efficiency of 65% and by implementing novel technologies developed in our group in excitonic solar cells we have achieved a threefold enhancement of the photocurrent conversion efficiency of a single junction photovoltaic device.





 

Quantum Optoelectronics

We investigate the interactions of light and matter in an environment of strong optical and electronic confinement. By spatially localizing photons and electrons in a very small  volume we modify their mutual interactions in a manner that gives rise to new optoelectronic properties. Semiconductor microcavities, the nanostructures used to confine photons and electronic excitations, are a new breed of optoelectronic device in which light and matter combine to create exciton-polaritons, unusual quasi-particles with fascinating properties.  The bosonic nature of polaritons and the unique characteristics of the microcavity could allow for demonstrations of Bose condensation, superfluidity and lasing in the solid state.  One aspect of this field with huge potential is the exploitation of polariton spin for use in spintronic devices.