Problem sheets: - The exercise sheets will be uploaded weekly to this website, on Thursday afternoon. - The solved exercise sheets must be submitted before the next Thursday lecture, via email to all four tutors.
This course provides an overview of an exciting and emerging field of research: quantum information theory and quantum technologies. The field is driven by the observation that single quantum systems, when used as elementary carriers of information, enable entirely new modes of information processing and communication—modes that differ fundamentally from their classical counterparts. Quantum key distribution, for example, allows communication in a manner that is secure against eavesdropping by unauthorized parties. Quantum simulators have the potential to outperform classical supercomputers in certain simulation tasks. Meanwhile, quantum computers—once only anticipated but now rapidly developing—can solve not all, but specific computational problems that remain intractable for classical machines. This course offers a comprehensive overview of these developments. At its core is a focus on methodological foundations, building on the principles of quantum theory. At the same time, we emphasize that quantum information is not merely about information processing, but also represents a powerful conceptual framework—a mindset that can be applied to problems in other fields, most notably in condensed matter physics, with which it is deeply intertwined. Finally, we will explore modern and recent advances in this rapidly evolving area.
Content:
1. Introduction 1.1 Some introductory words 1.2 Quantum information: A new kind of information?
7. Quantum key distribution 7.1 BB84 scheme 7.2 Entanglement-based schemes 7.3 Words on quantum technologies
8. Elements of quantum computing 8.1 Why quantum computing? 8.2 From classical to quantum computing 8.3 Gottesman-Knill and Solovay-Kitaev theorems
9. Quantum algorithms 9.1 Deutsch and Deutsch-Jozsa algorithm 9.2 Grover’s database search algorithm 9.3 Exponential speed-up in Shor’s factoring algorithm 9.4 Quantum algorithmic primitives and modern developments
10. Quantum computational models 10.1 Adiabatic quantum computing 10.2 Measurement-based quantum computing 10.3 Further models of quantum computing
11. Quantum error correction 11.1 Peres Code 11.2 Shor code 11.3 Elements of a theory of quantum error correction 11.4 Stabilizer codes and the toric code