Together with the CASA Cluster of Excellence (RUB University), ML4Q contributed to the Summer Schoon on Quantum Computing which took place two weeks ago at the Physikzentrum in Bad Honnef.
Venue: Physikzentrum Bad Honnef, Germany.
Date: August 14-19, 2022.
Organizers: Andris Ambainis (University of Latvia), David Gross (University of Cologne), Michael Walter (Ruhr University Bochum).
Important links: Official homepage, PDF program, 🍿 YouTube Playlist 🍿, 📖 Lecture Notes, Slides, References 📝.
This school gave an introduction to the theory of quantum computing. Quantum computing combines quantum physics and computer science into a new computing paradigm that promises to be fundamentally more powerful than any ordinary classical computer. It is currently a major focus of university departments, leading technology corporations, and nation states – driven by the discovery of novel quantum algorithms and promising progress on quantum hardware.
The school’s lectures were given by international experts at the forefront of quantum computing research. It started by introducing the mathematical model of quantum computers and fundamental concepts of computer science. Based on this, the school gave a panorama of important algorithms and state-of-the-art applications of quantum computing – ranging from quantum simulation to optimization. Further topics include quantum fault-tolerance, which is crucial for realizing quantum software on noisy hardware. In the past few years, the field has seen the emergence of quantum programming frameworks; these were introduced with hands-on tutorials, giving further opportunity for algorithmic practice. In addition, participants got a high-level overview of the state of quantum computing hardware from a prominent experimental expert.
The school included a networking event for women in quantum technologies, an evening discussion on quantum computing in industry, and an excursion to the quantum computing labs of the ML4Q collaboration.
Owing to the highly interdisciplinary nature of the field, the school was accessible to participants with a background in physics, computer science, or related disciplines. The target group of the school were Master & PhD students as well as starting postdocs.
- Simon Apers (IRIF, CNRS, Paris, France): Quantum Algorithmic Techniques and Quantum Walks
- Rami Barends (FZ Jülich, Germany): Quantum Computing with Superconducting Qubits
- Sevag Gharibian (Paderborn University, Germany): Classical and Quantum Complexity Theory
- András Gilyén (Rényi Institute, Budapest, Hungary): Quantum Machine Learning and Grand Unification of Quantum Algorithms
- Ashley Montanaro (University of Bristol & Phasecraft, United Kingdom): QAOA, VQE, NISQ and Combinatorial Optimization on Quantum Computers
- Barbara Terhal (TU Delft & QuTech, the Netherlands): Quantum Error Correction and Fault Tolerance I/II
- Inés de Vega (IQM, München): Quantum Computing Beyond Academia: Opportunities and Challenges
- Christa Zoufal (IBM Zürich, Switzerland): Quantum Programming
- Ronald de Wolf (CWI, University of Amsterdam & QuSoft, the Netherlands): Introduction to Quantum Computing, Grover Search and Applications
Lecture Notes, Slides, References
Ronald de Wolf:
- Lecture 1: Chapters 1-2, 4-5 of Ronald’s lecture notes.
- Lecture 2: Chapter 7 & Exercise 8.5 of the same lecture notes.
- Topological Quantum Memory by Dennis, Kitaev, Landahl, Preskill.
Proposing the toric code as quantum memory and showing how to decode and understand noise threshold.
- Quantum Error Correction for Quantum Memories by Terhal.
Older review of stabilizer quantum error correction with an emphasis on storing quantum information (rather than doing computation).
- Surface codes: Towards practical large-scale quantum computation, by Fowler, Mariantoni, Martinis, Cleland.
Review on surface codes which is partially outdated but still is a valuable introduction into the subject.
- Roads towards fault-tolerant universal quantum computation, by Campbell, Vuillot and Terhal.
Overview paper discussing the ideas on how to achieve fault-tolerant universal QC.
- A Game of Surface Codes: Large-Scale Quantum Computing with Lattice Surgery by Litinski.
Good overview of how to do logic via lattice surgery for a CNOT gate and an S gate for the surface code.
- Some recent experimental papers on quantum error correction for the surface code with superconducting qubits:
https://arxiv.org/abs/2112.03708 (ETH Walraff et al. group preserving a logical state with repeated QEC cycles), https://arxiv.org/abs/2102.06132 (Google AI team running the repetition code), https://arxiv.org/abs/2207.06431 (Google AI team running d=3 and d=5 surface code).