Scientists need individual photons for quantum cryptography and quantum computers. Leiden physicists have now experimentally demonstrated a new production method. Publication in Physical Review Letters on July 23rd.

‘We hope our paper highlights the possibilities and benefits of including artificial intelligence in quantum physics to do new discoveries.’ Vedran Dunjko of the Leiden Institute of Advanced Computer Science contributed to a paper that was published in PNAS last year and now received a Cozzarelli Prize…

Physicists understand little about quantum matter, which is a building block of future quantum computers. Theorists have now discovered that black holes with ‘dreadlocks’ harbor a similarly exotic order pattern, which makes calculations on quantum matter easier. Publication in Physical Review Letter…

Explore the profound impact of silences on social, political, and interpersonal dynamics in complex historical contexts. This collection of essays challenges assumptions and draws on diverse academic fields to reveal the pervasive nature of silence in human existence.

With Ad Putter, Sjoerd Levelt and Anne-Louise Avery. Based on William Caxton’s bestselling 1481 English translation of the Middle Dutch, but expanded with new interpretations, innovative language and characterisation, this edition is an imaginative retelling of the Reynard story. With its themes…

As of 1 June, Serge Fehr has been appointed as Professor Quantum information theory at the Leiden Mathematical Institute (MI). Fehr is employed by Centrum Wiskunde & Informatica (CWI) and as of his appointment works one day a week at the MI. Fehr’s research is focused on quantum cryptology and will…

How do we know what a quantum computer is good for when it hasn't been built yet? That's what PhD candidate Casper Gyurik investigated by combining two terms you often hear: quantum computing and machine learning.

The first larger quantum computers will soon be available. These computers need new software. Researchers at Leiden University have been awarded a Gravitation grant to develop the necessary software. They will be collaborating with colleagues from other research institutions.

Mass, time, space, and complexity — physicists in Leiden are launching eight new research projects tackling some of the most fundamental themes in quantum mechanics. Their goal: to push the limits of current quantum theories.

Quantum technologies are in demand worldwide, but until now Leiden students could not specialise in them. The new master’s program QIST (Quantum Information Science and Technology) is going to change that. Researcher and professor Jordi Tura i Brugués: ‘We need to train the next generation of quantum…

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.

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

Introduction to Medieval Europe 300–1500 provides a comprehensive survey of this complex and varied formative period of European history, covering themes as diverse as barbarian migrations, the impact of Christianisation, the formation of nations and states, the emergence of an expansionist commercial…

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…

There is no human society that does not employ a rich and diverse language. This course introduces you to linguistics, featuring interviews with well-known linguists and with speakers of many different languages. Join us to explore the miracles of human language!

Indo-European is the name of the language family to which English belongs, along with many sub-families such as Germanic languages and Romance languages. In this course, you will delve into the structure and origins of these branches, the oldest languages belonging to the language family, linguistic…

When many people think of slavery, they think of the translatlantic trade that took place between Africa, the Americas and the Caribbean.

How did the mythical kings of ancient Persia live? In this podcast, we delve into the Shahnameh, also known as the Book of Kings.

A suitcase covered with stickers from various universities, containing a quantum light source. Since April 2024, this suitcase has been visiting scientists in Europe researching single photons: the smallest possible quantity of light. The suitcase, also called ‘Q-torch’, travels from lab to lab like…

What does the future of quantum look like? Vedran Dunjko (Assistant professor at LIACS and LION) is co-founder of the applied quantum algorithms (aQa) leiden interdepartmental initiative research that will investigate this. They are part of the Quantum Delta NL consortium that was recently awarded substantial…

Much of the work of Serge Fehr, Professor of Quantum Information Theory, is abstract and theoretical and comprehensible to very few people. But his work helps make the digital world safer so that in future our internet banking will still be problem free, for instance. He will explain more in his inaugural…

Physicist Kaveh Lahabi’s research on quantum materials led to the launch of a new company: QuantaMap. With his colleagues, he developed a sensor that will improve the production of quantum computer chips. ‘It turns out that what I need for my fundamental physics research is also very useful for the…

At the center of this research project lies a practice-based, artistic exploration of the impact of digitalization on the lived reality of both physical and cognitive labor.

PhD defence

This year's Nobel Prize in Physics goes to quantum physics research. The prize will be awarded on December 10 in Stockholm. Physicist Bas Hensen explains why this is important and how his research in Leiden relates to it.

Watching and analysing hundreds of TEDx talks, that too can be research. That becomes clear from the work of PhD student Aletta Meinsma, who is studying potential problems in popular communication about quantum technologies. She explains how she approaches this and why it is so important.

The main topic of this PhD thesis is the Arakelov ray class group of a number field, an algebraic object that contains both the ideal class group structure and the unit group structure.

This special issue focuses on emerging trends in the implementation of the WPS agenda. In reviewing the resolution 20 years since the passing of Resolution 1325, Newby and O'Malley have highlighted the gaps in implementation.

Optical detection of a single electron using a single molecule has never been done. Leiden physicist Michel Orrit and his team have now identified a molecule that is sensitive enough to detect an electron at a distance of hundreds of nanometers. The results are published as a cover article in ChemPh…

The most famous cat in science is Schrödinger's cat, the quantum mechanical mammal, which can exist in a superposition, a state that is alive as well as dead. The moment you look at it, one of both options is chosen. Leiden University physicists simulated an experiment to catch this mysterious moment…

Assistant Professor Vedran Dunjko and his team receive a €100,000 gift from Google to support them in their quantum research. The research focuses on whether quantum computers can provide new ways of understanding the mysteries of high-energy physics. Google is committed to supporting ambitious research…

Our banking, DigiD and sensitive medical data: what if our entire digital infrastructure can no longer be trusted? Jelle Don has this question permanently in mind as he goes about his research. And that is no bad thing because without new digital security measures, our society will be extremely vuln…

Over the past two years, the Physics department has been supporting high school physics education with a set of challenging quantum experiments. School classes can visit Leiden University to learn about quantum mechanics, in preparation for their final exams. As of early 2018, this lab has evolved into…

During the Bachelor Honours Class ‘The world is quantum’, students from various disciplines learned about the rules of nature on the smallest scale: quantum mechanics. What opportunities and dangers do they see for their field of study?

Former PhD, Bachelor and Master students of the Van Exter Lab

Understanding interactions in quantum many-body systems remains one of the most profound and difficult challenges in condensed matter physics.

PhD defence

In the thesis we demonstrated an 85% state transfer efficiency between two mechanical modes coupled to a common optical mode via stimulated Raman adiabatic passage (STIRAP) in the classical regime. We also showed possibilities to manipulate quantum states of the mechanical modes via STIRAP.

Quantum technology, statistics and a survey with memes: definitely not your everyday research. Julia Cramer (Leiden Institute of Physics) and Sanne Willems (Institute of Psychology) investigate how people perceive quantum.

Petr Steindl works on quantum dots in microcavities for his PhD research. He manipulates single-photons to create complex structures of light. Applications could include quantum communication and gates for quantum computers.

We use DNA strands to stabilize few-atom silver clusters, which show unique optical and chemical properties. This thesis involves the study of these constructs for various applications.

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…

We investigate how radiation pressure can be used to influence the mechanical motion of a micro-mirror suspended from springs.

A suitcase as a messenger of quantum science. That is the idea behind QuanTour, a project connecting researchers from 12 European universities. In December, the suitcase landed in Leiden. A month later, it is time to pass the baton to Copenhagen. But what happened to it in Leiden?

Koen Bastiaans and his colleagues discovered a new quantum liquid unlike anything ever seen. They did it by using a technique that can be compared to listening to the sound of raindrops falling on a roof. Publication in Science 29 October.

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…

An international collaboration, including Leiden physicist and computer scientist Vedran Dunjko, showed that quantum technology can speed-up the learning process of artificial intelligence (AI). To prove this, the physicists and computer scientists used a quantum processor for single photons. Their…