The worldwide race to the quantum computer is in full swing. This computer can take on computing tasks that we can only dream of today, such as finding proteins that can be used as medicines in seconds flat. Leiden physicists have discovered how the Majorana particle can be used as a building block…

This thesis covers several aspects of quantum algorithms for near-term quantum computers and its applications to quantum chemistry and material science.

This thesis is a collection of theoretical works aiming at adjusting quantum algorithms to the hardware of quantum computers.

The NEASQC project brings together academic experts and industrial end-users to investigate and develop a new breed of Quantum-enabled applications that can take advantage of NISQ (Noise Intermediate-Scale Quantum) systems in the near future. NEASQC is use-case driven, addressing practical problems…

This thesis covers various applications of topology in condensed matter physics and quantum information.

Promotor: C.W.J. Beenakker, Co-Promotor: A.R. Akhmerov

Machine learning - on classical computers- has made great progress in the past five years. Computer translation of speech and text is just one example. In Leiden, some researchers expect that machine learning, empowered by quantum systems, even if they only contain a few dozen qubits, can lead to a…

Quantum annealing belongs to a family of quantum optimization algorithms designed to solve combinatorial optimization problems using programmable quantum hardware. In this thesis, various methods are developed and tested to understand how to formulate combinatorial optimization problems for quantum…

Top scientists of three Dutch universities are working on software and systems for quantum computers. Researchers of the Leiden Institute of Advanced Computer Science (LIACS) and the Leiden Institute of Physics (LION) are developing new algorithms to make those super computers work. The coming years,…

Can we use quantum computers in a way that is also relevant to society? With the help of a 2-million-euro NWA grant, Leiden University will work with partners such as Surf, Google and Volkswagen to demonstrate that quantum computers are also of value outside the lab.

Physicist Martin van Exter works with light at nanoscale, at the forefront of nanocomputer research. But as Director of Education he also has a vision for physics teaching. Inaugural lecture 18 November.

The aim of this thesis is to present novel techniques for proving cryptographic schemes secure against quantum adversaries. Most results are within the context of an idealized model called the ‘quantum random-oracle model’.

The 18.8 million euro NWO Zwaartekracht grant for quantum software which Amsterdam, Delft and Leiden landed collectively, means for Leiden University among others the appointment of two new permanent scientific staff members, who will each form their own research group, divided among Computer Science,…

This thesis investigates the contribution of quantum computers to machine learning, a field called Quantum Machine Learning. Quantum Machine Learning promises innovative perspectives and methods for solving complex problems in machine learning, leveraging the unique capabilities of quantum computers…

In this work we describe three methods to improve the performance of Quantum Field Theory calculations.

Quantum computing is an emerging technology, which holds the potential to simulate complex quantum systems beyond the reach of classical numerical methods.Despite recent formidable advancements in quantum hardware, constructing a quantum computer capable of performing useful calculations remains challenging.In…

This thesis addresses questions on effectively using variational quantum circuits for machine learning tasks.

Research groups in the Quantum Matter & Optics programme investigate electronic properties of matter and light-matter interactions with emphasis on quantum information.

Europe's latest quantum computer is set to arrive in the Netherlands. The Dutch IT cooperative, SURF, which supports education and research institutions, has secured funding from the European EuroHPC programme to make this possible. Researchers from Leiden University will play a key role in the project,…

Researchers found a way to run programmes that should be impossible to carry out on an imperfect quantum computer. Such programmes are very computationally demanding and the quantum computers that currently exist are not yet up to that task. Unless you use a clever trick, Simon Marshall and Vedran Dunjko…

In a global effort, quantum computers are rapidly being developed. In the meantime, researchers have to learn how to write code for these devices, which are fundamentally different from conventional computers. A collaboration of scientists led by Google, and including physicists from Leiden and Delft,…

Leiden physicist Julia Cramer receives 50 thousand euros in funding for 'Let's talk about quantum', a research project on communication about quantum computing. A project for high school students by education expert Henk Buisman is also included in the NEWA ELSA funding.

Quantum hardware comes with a different computing paradigm and new ways to tackle applications. Much effort has to be put into understanding how to leverage this technology to give real-world advantages in areas of interest for industries such as combinatorial optimization or machine learning.

The standard approach to build a quantum computer with Majoranas as building blocks is to convert them into qubits. However, a promising application of quantum computing—quantum chemistry—would require these qubits to be converted again into so-called fermions. Physicists from Leiden and Delft suggest…

The quantum computer is on its way, but is society ready for it? Quantum computers have a reputation of being difficult to grasp because of their complexity. This limits society’s ability to envision future applications creating a gap between society and quantum computers. A consortium of 14 knowledge…

The race to build the first quantum computer is still ongoing, but Morten Bakker has made big step forward in that process with qubits. A qubit is a unit of quantum information that can be produced in large numbers on chips. Qubits capable of exchanging photons (light particles) could be used in the…

With the help of quantum mechanics, digital quantum hardware may be able to tackle some of the problems that are too difficult for ordinary computers. But despite these expectations and the ongoing effort of the research community, reliable quantum computers are not yet realized in a lab setting.

With defending his thesis ‘Applications of topology to Weyl semimetals and quantum computing’, the Leiden theoretical physicist Tom O'Brien has gained the rare 'cum laude' qualification. The freshly minted PhD has started a five year research programme on quantum algorithms for quantum chemistry, funded…

Quantum computing is a novel paradigm for computation, which is nearing real-world impact with the coming generation of limited, but nonetheless powerful quantum devices.

Most of current public-key cryptography is considered insecure against attacks from sufficiently powerful quantum computers. Post-quantum cryptography studies methods to secure information resistant against such attacks. One proposal is isogeny-based cryptography, which bases its security on computational…

A single self-assembled semiconductor quantum dot in a high-finesse optical microcavity - the subject of this thesis - is an interesting quantum-mechanical system for future quantum applications. For instance, this system allows trapping of an extra electron and thus can serve as a spin quantum memory,…

Vedran Dunjko appointed to full professor of quantum computing at Leiden University, the Netherlands.

American physicist and quantum computing pioneer Seth Lloyd is the 65th Lorentz professor. He will deliver the Ehrenfest lecture on 5 June, and several more lectures on quantum computing on 11, 18 and 25 June.

The Divide & Quantum (D&Q) project offers various solutions to harness the power of quantum computers in the near term, proposing entire pipelines, from theoretical research, via implementation to real-world case studies in a number of disciplines, to science communication with the broader society.…

The Leiden Institute of Advanced Computer Science (LIACS) is a proud member of the NExt ApplicationS of Quantum Computing (NEASQC) consortium, which recently received an ERC H2020 grant to stimulate the state-of-the-art in industrial quantum computing. LIACS contributes research and development of new…

The worldwide race to the quantum computer is in full swing. This computer can bring about a breakthrough in discovering medicines and new materials. Leiden researchers, together with the TU Delft, are taking part in the race. There is now a dossier online about their work.

A major grant for research into machine learning algorithms for quantum computers. With this ERC Consolidator grant, Vedran Dunjko and his colleagues hope to discover which real-world problems a quantum computer can solve faster than a normal one.

Shell cooperates with theoretical physicists and chemists of Leiden University to research how quantum computer algorithms can help simulate complex molecules.

The quantum nature of matter and light has grown into a broad and fruitful research field for theorists and experimentalists alike. It combines foundational research with toward applications, the most well known of which is the quantum computer.

The quantum nature of matter and light has grown into a broad and fruitful research field for theorists and experimentalists alike. It combines foundational research with toward applications, the most well known of which is the quantum computer.

Quantum computers deserve their own quantum internet. This is a network that dispatches information not in the form of bits - ones and zeros - but rather as qubits, just like in the quantum computer itself. In the view of Dirk Bouwmeester, a professor in Leiden’s Quantum Matter & Optics research group,…

Quantum Delta NL, a research programme in which Leiden University participates, has been awarded 615 million euros from the National Growth Fund to help develop the Netherlands into a top player in quantum technology.

Quantum Information Science & Technology (QIST) encompasses the understanding, design, construction and investigation of quantum information processing systems, such as quantum computers, quantum communication networks, and quantum sensors.

Why do black holes emit thermal radiation? And how does a closed quantum system thermalize?