Theory — Atomistics

On this page, we present the fundamental atomistic theoretical models that underpin QTCAD. Broadly speaking, these models can be divided into two categories: models to construct and manipulate the atomic structures of heterostructure quantum dots, and models to describe the electronic structure of these atomic structures. The first four sections below are related to the first category, while the last two sections are related to the second category.

In Section 1, we describe the crystallographic unit cell of the zincblende crystal structures, which serves as the basic building block of atomic structures in QTCAD. In Section 2, we describe the random rough surface model used to generate disordered heterointerfaces. In Section 3, we describe how to construct atomic structures by tiling the unit cell, taking into account realistic disorder such as random alloying and rough heterointerfaces. In Section 4, we describe the Keating valence force-field model used to relax atomic structures.

In Section 5, we describe the tight-binding model used to resolve the electronic structure of heterostructure quantum dots. Finally, in Section 6, we describe how the \(g\)-tensor is computed within the tight-binding model.

• 1. Unit cells
• 2. Random rough surfaces
• 3. Atomic structures
• 4. Keating valence force-field model solver
• 5. Tight-binding Schrödinger solver
• 6. \(g\)-tensor solver