The overarching challenge for QuSoft is to harness the power of quantum information, through the study of quantum information science and the development of quantum algorithms. A particular focus is the design and development of protocols for quantum computation and quantum communication that can be run on small and medium-sized qubit platforms.
QUSOFT RESEARCH LINES

1. Quantum simulation and few-qubit applications
This research line addresses applications of small and medium-sized qubit platforms (10-100 qubits). In quantum simulation one uses such systems as analogue versions of quantum computers, allowing the study of problems in quantum chemistry and material science, among others. Few-qubit algorithms implemented on 50 or more qubits quickly become intractable for classical computers. This research line also addresses multi-qubit dynamics and quantum control, with applications in the design of quantum registers and in quantum many-body physics.
Senior Researchers: Harry Buhrman, Jean-Sébastien Caux, Vladimir Gritsev, Eric Opdam, Kareljan Schoutens, Florian Schreck, Michael Walter and Jasper van Wezel
Affiliate researchers: Philippe Corboz, Klaasjan van Druten, Rene Gerritsma, Robert Spreeuw and Jasper Stokman
Postdocs: Benjamin Pasquiou and Georgios Siviloglou
PhD candidates: Tom Bannink, Shayne Bennetts, Chun-Chia Chen, Alessio Ciamei, Koen Groenland, Joris Kattemölle, Oleksiy Onishchenko, Sergey Pyatchenkov, Bart van Voorden and Freek Witteveen.
2. Quantum information science
This research line addresses the broad range of insights and questions that arise as soon as information is processed according to the rules of quantum mechanics. Reasoning based on quantum notions such as superposition and entanglement leads to applications in computer science, mathematics, logic and physics that do not always need an actual physical device. Some successful examples: an optimal algorithm for matrix multiplication, solving problems in operator algebras and functional analysis, and error-correcting codes. In the realm of physics, quantum information can be used in the study of non-locality, quantum thermodynamics, condensed matter systems, and even the structure of space-time itself.
This research line also addresses quantum network and communication protocols, and distributed quantum computation. We study quantum-classical systems as well as architecture, interfaces and control.
Senior Researchers: Jop Briët, Harry Buhrman, Mark Golden, Erik van Heumen, Monique Laurent, Maris Ozols, Cees de Laat, Paola Grosso, Leen Torenvliet, Michael Walter, Christian Schaffner and Ronald de Wolf
Affiliate researchers: Hans Maassen, Bernard Nienhuis and Sonja Smets
Postdocs: Christian Majenz
PhD candidates: Bas Dirkse, Sander Gribling, Farrokh Labib and Jeroen Zuiddam
3. Cryptography in a quantum world
This research line is double-edged. One edge, known as post-quantum cryptography, is the development of cryptography that is difficult to break for attackers armed with large quantum computers. The goals are to improve existing schemes for this, to develop new efficient quantum-safe protocols and to analyse attacks that can be run on large quantum computers. The other edge, known as quantum cryptography, is the design and investigation of protocols that solve cryptographic problems that involve quantum data and quantum communication.
Senior researchers: Harry Buhrman, Serge Fehr, Stacey Jeffery, Christian Schaffner and Michael Walter
Postdocs: Christian Majenz
PhD candidates: Jan Czajkowski, Yfke Dulek, and Jeroen Zuiddam
4. Quantum algorithms and complexity
Which computational tasks are amenable to quantum speed-up? This research line addresses this fundamental question and develops and investigates new quantum algorithms. This activity is focused on the many-qubit regime, where full-fledged error correction and fault tolerant computation becomes possible. Important research questions are the verification and debugging of quantum algorithms – the very nature of quantum computing preempts methods known from classical computer science and calls for fundamentally new strategies and protocols.
Senior Researchers: Jop Briët, Harry Buhrman, Stacey Jeffery, Maris Ozols, Michael Walter and Ronald de Wolf
Affiliate researchers: Femke van Raamsdonk
Postdocs: Alex Bredariol Grilo, Yinan Li and Mathys Rennela
PhD candidates: Joran van Apeldoorn, Tom Bannink and András Gilyén