1.
J Phys Condens Matter
; 28(22): 224005, 2016 06 08.
Artigo
em Inglês
| MEDLINE
| ID: mdl-26952789
RESUMO
The question of optical bandgap anisotropy in the monoclinic semiconductor ß-Ga2O3 was revisited by combining accurate optical absorption measurements with theoretical analysis, performed using different advanced computation methods. As expected, the bandgap edge of bulk ß-Ga2O3 was found to be a function of light polarization and crystal orientation, with the lowest onset occurring at polarization in the ac crystal plane around 4.5-4.6 eV; polarization along b unambiguously shifts the onset up by 0.2 eV. The theoretical analysis clearly indicates that the shift in the b onset is due to a suppression of the transition matrix elements of the three top valence bands at Γ point.