New publication from the SUNLAB: Progress in Photovoltaics

In a recent article first-authored by former postdoctoral fellow Meghan Beattie in collaboration with the Fraunhofer Institute for Solar Energy, researchers demonstrate a three-step reverse voltage biasing external quantum efficiency method (EQE) which measures any number of subcells with overlapping absorptance. They demonstrate this approach for a two-junction GaAs-based photonic power converter, comparing to the standard light biasing method and revealing better than 0.8% absolute agreement when the top junction is preferentially biased in the reverse voltage biasing method. They demonstrate the viability of the method by measuring the EQE of all subcells in a six-junction GaAs-based photonic power converter.

Click here for the full article in Progress in Photovoltaics: Research and Applications.

M. B. Beattie, M. Schachtner, G. Siefer, D. Lackner, O. Höhn, K. Hinzer, and H. Helmers, Subcell-resolved EQE method using reverse voltage biasing for multijunction photovoltaics with overlapping subcell absorptance, Prog. Photovoltaics: Res. Appl., Early View (2025). DOI: 10.1002/pip.3914.