Wednesday, 27 October 11:00am – 12:00pm

This seminar will be delivered via Zoom – Please email chemistry.researchsupport@sydney.edu.au for zoom link and password.

Speaker: Associate Professor Jacob Krich; The University of Ottawa

Host: Associate Professor Ivan Kassal

Title: Intermediate band materials: Requirements for high efficiency solar cells and mid-IR plasmonics

Abstract: An intermediate band (IB) material has a band gap, like a semiconductor, but also has an extra set of allowed electronic levels inside the gap, allowing subgap light absorption. IB solar cells have the potential to give the high efficiencies of triple-junction devices with a simpler design. Yet an efficient IB solar cell has not yet been realized. I will introduce Simudo — the first device model to treat all the essential physical processes of IB materials — and a semianalytic model for IB devices. I will show the material properties and figures of merit required for effective IB solar cells and compare to existing IB materials, indicating which are most promising. I will present promising experimental and theoretical results on GaN/InGaN quantum dot devices, showing their relatively strong 2-photon photocurrent production as well as how they can be adapted to form a ratchet band solar cell. Finally, I will discuss the interesting plasmonic properties of IB materials, focusing on the case of highly mismatched alloys.