Acknowledgements

Dedicated to my parents, Ewara and Paul

The writing of this thesis and the work behind it was supported by many people I wish to acknowledge:

I thank Prof. Siegfried Selberherr who laid trust in my abilities and gave me the opportunity to conduct research at the Institute for Microelectronics. He provided me with working conditions where I can truly claim that I was the only limitation to what I have achieved. The funding he ensured was there allowed me completely focus on my research and to attend multiple conferences around the world where I could interact with leading researchers. His meticulous proofreading (also shortly before deadlines) ensured that I always strived towards writing high quality manuscripts and shall continue to do so.

My scientific supervisor Mihail ”Mixi” Nedjialkov put almost as much work into this thesis as I have. His research on the topic of Wigner Monte Carlo simulations over many years laid the groundwork for me to explore a stimulating and exciting research topic where he allotted me plenty of freedom. He was extremely generous to me in many ways, especially with his time (even on Friday afternoons – his favourite time of the week to face my questions and sometimes argumentative nature). It was a true pleasure for me to have had a scientific mentor with a visible passion for his research and who always was ready to crack a joke. Thanks, Mixi – you are the best!

I thank Josef Weinbub for his support in the parallelisation of my code and general support in the development of the ViennaWD software – without his help I would still be waiting for my simulations to finish! I wish to acknowledge also the contributions Matthias Glanz made to improve the usability of my Wigner Monte Carlo simulator. I thank also Thomas Windbacher for greatly refining my German version of the abstract.

I appreciated the interest and input I received on my field of research from Prof. Hans Kosina, Zlatan Stanojević and Oskar Baumgartner. The same holds true for Viktor Sverdlov who also kept an eye out for me, also outside of the office.

External to the institute, I thank Prof. Dave Ferry (Arizona State University) and Prof. Irena Knezevic (University of Wisconsin-Madison) for their valuable feedback on my work and their enthusiasm for research relating to the Wigner formalism. I especially thank Prof. Ivan Dimov (Bulgarian Academy of Sciences) for taking an interest in my work and, ultimately, acting as the external examiner of my thesis.

Many people contributed to making the institute a pleasant place to work: I thank Prof. Erasmus Langer who allocated a calm office space to me in which I could be productive. I also thank Ewald Haslinger and ”Frau Winkler” for tolerating the constant stream of (sometimes heavy) post I had coming to the office. Manfred Katterbauer always kept all the infrastructure running at our institute with a smile, which I appreciated. I also thank Lado Filipovic who was always there to show me the intricacies of the ESS administration system before I even had the opportunity to ask.

It was a pleasure for me to work in an environment which was positive, friendly and supportive in many ways. I thank all my colleagues of present and past for this and for making the many social gatherings at the office and at conferences lots of fun.

I shared my office with Johann Cervenka who supported me with ad hoc solutions to all my computer problems and always was ready for a joke or a chat. Outside the office he was at least just as supportive, always ready to accompany me for round N + 1. I also thank Rüdiger Sonderfeld, a friend whom I made at the office, for showing me what German efficiency is all about. I thank Prateek Sharma, a colleague and now a valued friend, with whom I faced the daily onslaught of food in the canteen. He often had to endure my rants and not so funny jokes. I also fondly remember the many hours I spent cycling around Austria with my former colleague Dmitri Osintsev – it was a real joy!

Also people outside of the institute supported me, for which I am grateful: Olga and Ievgen welcomed me to Vienna with great hospitality and have been true friends. I thank Angela for allowing me to sit on her ridiculously large terrace and ensuring I do not only talk to scientists and engineers every day. I had the pleasure of many friends visiting me over the years in Vienna – some from very far away. Their visits always provided a welcome change to my daily routine. I specifically thank Alessandro, Karen, Kasia, Konrad, Devon and my compadre Danilo. Also, I thank my friends Soheil and Richard for inviting me to visit them and their continued friendship. I thank my flatmate, Izabela, for not causing too much trouble overall and putting up with my often ’sunny’ demeanour in the mornings.

Moving further afield, I am grateful to my family and friends in Pretoria who always welcomed me back home. Especially I thank my cousins Frans and Hein who always found time for a live or virtual ”multisession”. I am also grateful to my cousin Rosan and her husband Vincent – my family not quite so far away from home – for their support and always making me feel welcome in their house.

Lastly, I express my deepest gratitude to my mother whose unconditional support I have enjoyed my entire life. Since I have been away from home, she took on many responsibilities which I should have shared with her. My parents have instilled qualities in me from which I have already benefited so much in my life – I am eternally thankful to them.

Paul Ellinghaus

Vienna, February 2016