Dr Adam Jackson, University College London
Transparent conducting oxide (TCO) coatings are being deployed on a dramatic scale as part of opto-electronic devices and low-emissivity window treatments. The wide-bandgap oxide GaSbO4 has appealing properties as an indium-free transparent conductor, offering alternative structural and electronic alignment. Early experiments have assigned a “random rutile” structure, but it is difficult to reconcile this with the wide measured optical bandgap. Theoretical methods including cluster-expansion and hybrid density-functional theory can be used to explore the fundamental properties of this material and their sensitivity according to different structural models. A greater challenge lies in relating these simulations to experimental measurements in order to definitively assign a structure. For practical purposes it appears possible to synthesize an ordered material with a suitable electronic structure for n-type TCO applications.