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

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

In this thesis, classes of strongly interacting quantum field theories, have been studied.

Promotor: K.E. Schalm, Co-promotor: S.S. Lee

The focus of our theoretical physics research is the nature of macroscopic matter that is in one or the other way still in the grip of quantum physics.

Promotor: Ronald Cramer, Co-promotor: Serge Fehr

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

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,…

Schalm

Promotor: Prof.dr. D. Bouwmeester, Co-promotor: M.P. van Exter

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

Promotor: C. W. J. Beenakker, Co-promotor: J. K. Asboth

Promotor: R. Gill, Co-promotor: P. Massart

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.

We study the dynamics of individual emitters in micro cavities.

Promotor: H.W. Lenstra, Jr., Co-promotor: B. de Smit

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

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.

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

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…

Majorana meets a mermaid

During my PhD research, I studied the photon statistics of light emitted by a microcavity that contains a single quantum dot (QD) on resonance.

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.

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.

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,…

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.

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

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.

Many important topics in computer science, such as the correctness of software, the efficiency of algorithms and the modeling of complicated systems, depend on sound theoretical underpinnings. In the Theory group, we study these fundamental building blocks and develop verification methods to prove system…

Many important topics in computer science, such as the correctness of software, the efficiency of algorithms and the modeling of complicated systems, depend on sound theoretical underpinnings. In the Theory group, we study these fundamental building blocks and develop verification methods to prove system…

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

The research group ‘Quantum and Society’ explores the boundary between quantum technology and science communication.

Bouwmeester

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,…

On Wednesday September 26th, theoretical physicist Sean Carroll will give an Ehrenfest colloquium. It is part of a lecture series that has been running since 1912 and was founded by physicist Paul Ehrenfest.

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…

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,…

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 critical metals at vanishing fermion flavor number.

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).

PhD Defence

This thesis described the development of novel scanning tunneling microscopy techniques to investigate strongly correlated electronic states in quantum matter.

Advancing the understanding of the interaction of light and matter on the single-quantum level is important for near-future quantum technologies but also to answer fundamental questions.

The dissociation of CH4 into CH3 + H on a metal surface is the rate determining step in processes which produce hydrogen, such as steam reforming and catalytic partial oxidation. Ultimately, we want to study the dissociation of methane on Ni(111) and Pt(111) quantum mechanically while taking into account…

Promotor: Prof.dr. A. Achucarro, Co-Promotor: J.W. van Holten

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

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