Hot carrier extraction at Cu-GaN interfaces published in ACS Nano
G. Tagliabue, J. S. DuChene, A. Habib, R. Sundararaman and H. A. Atwater, “Hot Hole versus Hot Electron Transport at Copper/GaN Heterojunction Interfaces”, ACS Nano 14, 5788 (2020)
Copper’s excellent catalytic properties along with its CMOS compatibility makes it a promising candidate for future hot carrier devices. This paper reports a combined experimental and theoretical investigation of hot carrier extraction efficiency in copper, accounting for energy distribution after generation, subsequent transport in copper, and finally their injection into the gallium nitride (GaN) semiconductor. In particular, we use ab initio calculations of hot carrier generation and transport to extract injection probability at the interface from experimentally-measured internal quantum efficiency (IQE) for both hot electron and hot hole devices. We find that hot-hole photodetectors are ideal for operation in the ultraviolet to visible regime while hot-electron devices show significant reduction in performance above the interband threshold (approximately 2.1 eV). These results provide a comprehensive guide for designing efficient optoelectronic and photocatalytic systems using plasmon-generated hot carriers in copper.