Journal of the Vacuum Society of Japan
Online ISSN : 1882-4749
Print ISSN : 1882-2398
Symmetry Breaking-induced Band-splitting in GaAs Thin Film by First-principles Calculations
Mary Clare ESCAÑOHideaki KASAIMasahiko TANI
ジャーナル フリー

2017 年 60 巻 11 号 p. 445-449


 We investigated the band-splitting of GaAs thin film by invoking broken inversion symmetry within the bulk region and the lost of 2D symmetry on the surface due to strain in first-principles calculations using density functional theory with spin-orbit interaction. The system is modeled by unreconstructed GaAs(001)-(1×1) slab, and by its strained counterpart arising from As dimerization. For the unstrained system, we found that the valence bands split while the conduction bands remain degenerate. This degeneracy is attributed to the sole contribution of p-state of As atoms found on the surface to this band, where 2D symmetry is preserved. When strain is imposed on this surface, the symmetry is broken and the conduction bands are split. These findings identify the changes in the band structure due to broken symmetry, suggesting their incorporation in the conventional degenerate theoretical description of the GaAs thin films done to date.

© 2017 The Vacuum Society of Japan
前の記事 次の記事