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

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…

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

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’.

Onderzoeksgroepen in het Quantum Matter & Optics onderzoeksprogramma onderzoeken elektronische eigenschappen van interacties van materie en lichtmaterie, met de nadruk op quantuminformatie.

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

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

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…

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.

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…

Topwetenschappers van drie Nederlandse universiteiten werken samen aan software en systemen voor quantumcomputers. Onderzoekers van het Leiden Institute of Advanced Computer Science (LIACS) ontwikkelen nieuwe algoritmen om die supercomputers te laten werken. De komende jaren moet het eerste quantuminternet…

Volgens het standaardrecept voor een quantumcomputer met Majorana’s als bouwstenen moet je ze omzetten in qubits. Maar een veelbelovende toepassing van quantum computing—quantumchemie—vereist dat deze qubits opnieuw transformeren, in zogenoemde fermionen. Natuurkundigen uit Leiden en Delft stellen voor…

Chatten, internetbankieren of onderzoeksdata delen: cryptografie zorgt ervoor dat wij veilig kunnen interetten. Ook in oorlogen is het belangrijk dat informatie niet in verkeerde handen valt. Maar hoe lang zijn onze geheimen nog veilig? Hoogleraar Cryptologie Ronald Cramer vertelt over de gevaren en…