Component based method of ab initio simulation for nanoscale electronic devices and circuits
File(s)
Author(s)
White, Catherine
Type
Thesis
Abstract
This thesis describes the development of a numerical technique for handling quantum electronic transport equations in the ballistic regime in a way that generates physically meaningful and useful quantities about internal device current and coupling. This is achieved by using a Lippmann-Schwinger Tight-Binding transport model and applying it to a quantum device which we consider piecewise, as components or regions of the whole device. We derive the method and explain how it can improve the adjustability, reusability and efficiency of quantum simulation calculations.
The new method is an advance on the one dimensional method of surface Green functions which is a feature of many contemporary electronic transport codes, and shows how a fully flexible approach can be implemented in a modern code. Other fully 3D codes exist, but the new method is di erent because it is based on physical components. The new theoretical concept of a partial self-energy in a Lippmann-Schwinger equation is developed to enable the technique. We perform some illustrative calculations using the method.
The new method is an advance on the one dimensional method of surface Green functions which is a feature of many contemporary electronic transport codes, and shows how a fully flexible approach can be implemented in a modern code. Other fully 3D codes exist, but the new method is di erent because it is based on physical components. The new theoretical concept of a partial self-energy in a Lippmann-Schwinger equation is developed to enable the technique. We perform some illustrative calculations using the method.
Version
Open Access
Date Issued
2021-02
Date Awarded
2021-11
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Horsfield, Andrew
Sponsor
Engineering and Physical Sciences Research Council
Publisher Department
Materials
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)