Journal article
Strain sensitivity of band gaps of Sn-containing semiconductors
Tuning of band gaps of semiconductors is a way to optimize materials for applications within photovoltaics or as photocatalysts. One way to achieve this is through applying strain to the materials. We investigate the effect of strain on a range of Sn-containing semiconductors using density functional theory and many-body perturbation theory calculations.
We find that the band gaps of bulk Sn oxides with SnO6 octahedra are highly sensitive to volumetric strain. By applying a small isotropic strain of 2% (-2%), a decrease (increase) of band gaps as large as 0.8 to 1.0 eV are obtained. We attribute the ultrahigh strain sensitivity to the pure Sn s-state character of the conduction-band edges.
Other Sn-containing compounds may show both increasing and decreasing gaps under tensile strain and we show that the behavior can be understood by analyzing the role of the Sn s states in both the valence and the conduction bands.
Language: | English |
---|---|
Year: | 2015 |
ISSN: | 1550235x , 10980121 and 01631829 |
Types: | Journal article |
DOI: | 10.1103/PhysRevB.91.045204 |
ORCIDs: | Castelli, Ivano Eligio , Thygesen, Kristian Sommer and Jacobsen, Karsten Wedel |