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arXiv · 2309.06881

Calculating the Stability of Different Surfaces of GaAsxP1-x Mixed-Crystals using the Virtual Crystal Approximation

Marsel Karmo·Hartmut Grille·Isaac Azahel Ruiz Alvarado
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Abstract

The theoretical treatment of mixed-crystals is very demanding. A straight-forward approach to attack this problem is using a super cell method (SCM). Another one is the Virtual Crystal Approximation (VCA), which is a feature of the Vienna Ab initio Simulation Package (VASP). For comparison we use both methods to calculate the total energy (Etot) and the density of states (DOS) of bulk GaAsxP1-x. We then apply VCA to compute the stability of different surfaces using an extended version of the surface formation energy Omega. Our calculations show, on one hand, a working VCA implementation with its flaws (overestimation of Etot) and strengths (well modelling of DOS). On other hand, a further result is that bulk of the slab of a mixed-crystal has a minor influence on the configuration of the surface.

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Marsel Karmo, Hartmut Grille, Isaac Azahel Ruiz Alvarado. 2023-09-13. Calculating the Stability of Different Surfaces of GaAsxP1-x Mixed-Crystals using the Virtual Crystal Approximation. https://arxiv.org/abs/2309.06881

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