2003/11/19 by Seungwon Lee, Fabiano Oyafuso, Paul von Allmen +1 · 2 citations
Physics and Astronomy · #GaN-based semiconductor devices and materials #Quantum and electron transport phenomena #Semiconductor Quantum Structures and Devices #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.69.045316
20 pages, 9 figures
arxiv created 2003/11/19 · openalex publication_date 2004/01/26 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The modeling of finite-extent semiconductor nanostructures that are embedded in a host material requires a proper boundary treatment for a finite simulation domain. For the study of a self-assembled InAs dot embedded in GaAs, three kinds of boundary conditions are examined within the empirical tight-binding model: (i) the periodic boundary condition, (ii) raising the orbital energies of surface atoms, and (iii) raising the energies of dangling bonds at the surface. The periodic boundary condition requires a smooth boundary and consequently a larger GaAs buffer than the two nonperiodic boundary conditions. Between the nonperiodic conditions, the dangling-bond energy shift is more numerically efficient than the orbital-energy shift, in terms of the elimination of nonphysical surface states in the energy region of interest for interior states. A dangling-bond energy shift larger than 5 eV efficiently eliminates all of the surface states and leads to interior states that are highly insensitive to the choice of the energy shift.