Analytic many-body potential for GaAs(001) homoepitaxy: Bulk and surface properties

Abstract

We employ atomic-scale simulation methods to investigate bulk and surface properties of an analytic TersoffAbell type potential for describing interatomic interactions in GaAs. The potential is a modified form of that proposed by Albe and colleagues [Phys. Rev. B 66, 035205 (2002)] in which the cut-off parameters for the As-As interaction have been shortened. With this modification, many bulk properties predicted by the potential for solid GaAs are the same as those in the original potential, but properties of the GaAs(001) surface better match results from first-principles calculations with density-functional theory (DFT). We tested the ability of the potential to reproduce the phonon dispersion and heat capacity of bulk solid GaAs by comparing it to experiment and the overall agreement is good. In the modified potential, the GaAs(001) β2(2 × 4) reconstruction is favored under As-rich growth conditions in agreement with DFT calculations. Additionally, the binding energies and diffusion barriers for a Ga adatom on the β2(2 × 4) reconstruction generally match results from DFT calculations. These studies indicate that the potential is suitable for investigating aspects of GaAs(001) homoepitaxy.

Surface reconstruction stability and configurational disorder on Bi-terminated GaAs(001)

“…It is believed that adatoms diffuse along the dimer rows on the surface. 38 The (4×3) surface is comprised of different types of dimers, including As-As, Bi-Bi, As-Bi, As-Ga, Bi-Ga, depending on growth conditions. In addition, the distribution of these dimers on the surface lattice can vary considerably.…”

Accelerated molecular dynamics study of theGaAs(001)β2(2×4)/c(2×8)surface

“…We recently introduced a force field that is suitable to describe both bulk properties of GaAs and the GaAs(001)β2(2 × 4) reconstructions. 24 In the present paper, we employ this force field to describe the mechanisms leading to the long-range structure of GaAs(001)β2(2 × 4).…”

Strengthening Brittle Semiconductor Nanowires through Stacking Faults: Insights from in Situ Mechanical Testing

“…The available potential function of GaAs common polytypes such as 2H, 3C, and 4H was used in the MD simulations. 29 The simulation results are shown in Figure 4. In Figure 4a, GaAs NWs with the ZB (3C) and WZ (2H) structures fail after reaching the ultimate compressive stresses of ∼5.6 and 6.4 GPa (Figure 4a), respectively, in good agreement with the corresponding experimental results of ∼5.4 and 6.2 GPa.…”

“…Unfortunately, the MD potential function 29 was established based on several common GaAs polymorphs such as 2H, 3C, and 4H. While it describes the bond strength of these common polymorphs well, it fails to predict the bond strength at various SF sites in a 2H NW because it is difficult to adopt an appropriate potential function to describe all possible SF structures and the corresponding interfacial states.…”

“…In MD simulations, a modified Tersoff potential was used to model atomic interactions. 29 NWs with 3C, 2H, and 4H structures were generated by stacking the tetrahedral bonding of Ga−As with sequences of "ABC...", "ABAB...", and "ABAC...", respectively. 2H NWs with SFs were prepared by randomly inserting 3C and 4H units into the 2H matrix, with distance between neighboring SFs being 1, 3, 5, 7, and 10 nm.…”