The EPEE Lab works at the intersection of applied physics, electrical engineering, and materials science, with strengths in photonic and nanoelectronic devices.

Dilute Germanium Carbides: Simulation and Epitaxy
Adding 1% carbon to germanium is expected to create an alloy with a direct bandgap. This would enable on-chip lasers to overcome the “bandwidth bottleneck” in many-core CPU systems, allowing higher performance at lower power consumption. It would also reduce the size of silicon photonic integrated circuits, because the interaction with light (optical matrix element) is much stronger.

Core-Shell Upconverting Nanostructures (CSUNs)
Sunlight is free, but even in advanced solar cells, most of it is wasted. By efficiently converting several low-energy photons to a high-energy electron, photovoltaics can be made more efficient.

Heteroepitaxy on Silicon
What are the limits to growth of different semiconductors together? New growth techniques bypass traditional limits such as lattice mismatch, producing threading defect densities (TDDs) that are as low as in new wafers, despite 4% mismatch in lattice constant.

Tunneling Field Effect Transistors (TFETs)
Based on the advances listed above, we are modeling the performance of TFETs based on highly mismatched alloys. These would provide better performance for low power applications such as tablets and smartphones.

Please contact us if you are interested in one or more of these topics.