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’.

We study the dynamics of individual emitters in micro cavities.

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

Are quantum computers the scientific breakthrough of our time? In this podcast, Carlo Beenakker, Professor of Physics at Leiden University, explains quantum technology.

The research program of the QO group has three leading themes: Optical Physics, Quantum Optics, and Photon-Matter Interactions. We work mostly at the boundaries between these themes with entanglement as a bridging and binding agent.

Science journalist Anna Gimbrère and physicist Julia Cramer will open the Quantum Escape Room in Eindhoven on Wednesday, 17th of December. Researchers from Leiden worked closely with the designers to make sure the escape room is not only exciting, but also truly quantum.

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

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.

Welcome to the Hensen Lab! We are a young dynamic experimental research group starting at the Leiden Institute of Physics. Our lab addresses one of the key challenges of modern physics: understanding the interface between quantum mechanics and general relativity.

Born in Europe roughly 100 years ago, quantum physics brought forth a veritable technological revolution through semiconductors, lasers, fibre optics, and many other technologies that are today ubiquitous in our lives. Now, during the second quantum revolution, Europe can take the lead once more in…

In Quantum mechanics, particles can be in multiple positions simultaneously. Yet, when a measurement is made, the particle is found only in one place. Technology has come to a point where we may design experiments that will tell us how.

The master’s specialisation Research in Physics, Quantum Matter and Optics at Leiden University offers a thorough experience on the front line of physics research with a practical training of communicative and computer skills. The programme focuses on Condensed Matter problems, such as Molecular Electronics,…

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.

In my research, we developed a method to distinguish knots. A knot is a mathematical depiction of the everyday knot that occurs in ropes and cords.

Thermodynamics is one of the founding scientific pillars that has helped us better understand heat engines, biology, ecosystems, and even black holes. While it fundamentally describes large systems by examining the bulk behavior of their constituents, it is anchored in the statistical equivalence of…

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

Quantum computers are a proposed fundamentally new type of computer. They aim to perform some computations much faster than previously possible by exploiting phenomena at the quantum scale, called superposition and entanglement.

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…

Cambridge University Press has published a new book co-authored by researchers from Leiden University, offering both an introduction to machine learning and deep neural networks, and an overview of their applications in quantum physics and chemistry — from reinforcement learning for controlling quantum…

Quantum position verification (QPV) - the subject of this thesis - is a novel way to authenticate unknown nodes in a quantum network without the need to physically meet up.

Promotor: C.W.J. Beenakker, Co-promotor: M.T. Wimmer

PhD defence

This thesis investigates how quantum, quantum-inspired, and hybrid quantum-classical computation can enhance key points of the automated machine learning (AutoML) pipeline under the constraints of noisy intermediate-scale quantum (NISQ) devices.

The research group of Semonti Bhattacharyya at the Leiden Institute of Physics studies quantum transport measurements in Van der Waals heterostructures.

Promotor: Prof.dr.ir. J.W.M. Hilgenkamp, Prof.dr. J. van den Brink

This thesis advances automata learning, a key area in computer science, with applications in software verification, biological analysis, and autonomous technologies. It explores three main themes: first, it introduces a passive learning algorithm for generating compact probabilistic models from positive…

This master’s programme combines Physics with Data Science. You will learn how physics has its own tricks to deal with big data and how techniques from machine learning and deep learning can be applied to classical and quantum data. The first focus of attention is on classical data, including data mining,…

Kaveh Lahabi's lab explores the exotic physics of quantum materials, whose underlying physics seems to have more in common with elementary particles and black holes, than ordinary metals and semiconductors.

Our group explores the larger domain of quantum measurement. In particular we investigate two themes that are closely connected: The detection of specially prepared quantum states of light and understanding and characterizing quantum photon detectors.

In this dissertation, we work towards an experiment in which we aim to bring a micrometer sized magnet at the tip of a soft cantilever into a superposition.

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.

We are a dynamic research group at the Leiden Institute of Physics. Our aim is to explore and understand quantum materials, including strange metals, high-temperature superconductors, and quantum critical electron matter.

The focus of Jan Zaanen's theoretical physics research was the nature of macroscopic matter that is in one or the other way still in the grip of quantum physics.

Leader in law and technology education and research since 1985.

Ice, the solid state of water, plays an important role on our planet as well as the entire universe.Despite the fact that an individual water molecule has a very simple structure, its chemical bonding in the solid phase can be surprisingly complex.

Can you prove whether a large quantum system truly behaves according to the weird and wonderful rules of quantum mechanics — or if it just looks like it does? In a groundbreaking study, physicists from Leiden, Beijing en Hangzhou found the answer to this question.

Friday afternoon, 1 October. Location: one of the most vibration-free places in the world. In this setting, Leiden top scientists launched Quantum Leiden. For decades, researchers at the Faculty of Science have been investigating quantum technology at the highest level and also have been brainstorming…

We explore the possibilities to combine magnetic resonance techniques with atomic force microscopy together in a single microscope: the MRI-AFM, also called Magnetic Resonance Force Microscopy (MRFM).

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.

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. This has been announced at the presentation of the honoured proposals in The Hague…

This thesis considers multi-prover commitment schemes whose security is based on restrictions on the communication between the provers.

Promotor: Prof.dr. D. Bouwmeester, Co-Promotor: M.J.A. de Dood

In cryptography, generic transformations are often used to strengthen simpler but weaker schemes, into more sophisticated and stronger ones.

Quantum games aren’t just a fun way to explain quantum physics — they may also unlock new discoveries. According to physicist Evert van Nieuwenburg, these games create structure and clear rules. Simply playing them can even contribute to better quantum software.

Quantum technology has the potential to transform society. But how can you effectively inform the public about such complex and enigmatic science and technology? PhD candidate Aletta Meinsma explored this.

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 critical metals at vanishing fermion flavor number.

In our lab, we investigate the physics and material properties of low-dimensional systems.