Single-molecule spectroscopy has become a powerful method for using organic fluorescent molecules in numerous applications.

Detecting nanoscopic objects plays an important role in nanoscience in particular, in the rapidly growing field of nanobiology. The forebear to modern super-resolution microscopy for single molecule investigation, is fluorescence microscopy.

Single-layer graphene (SLG) has attracted considerable interest as a proton exchange membrane for direct methanol fuel cells (DMFCs), owing to its atomic thickness, mechanical robustness, and unique proton permeability.

Promotor: E.R. Eliel, Co-Promotor: M.J.A. de Dood

This thesis focused on the exploration of monolayer graphene as a membrane in direct methanol fuel cell (DMFC) applications, with improvements achieved through plasma exposure or damage- free chemical functionalization.

The single cell group (SCG) is part of the Metabolomics & Analytics Centre Our research is centered around developing innovating analytical methods tailored for small-volume, or single cell analysis to enable metabolomics-driven systems biology in personalized health strategies. We are always on…

Ariadne Schmidt, Isabelle Devos and Julie de Groot provide you with refreshing insights concerning the study on urban singles in the period between 1200 and 1900.

Promotores: Prof.dr. D. Bouwmeester, Prof.dr. A. Fiore (TU Eindhoven)

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.

The results of the investigations by citizens are used in an innovative research project that investigates the potential of machine learning and automated detection in archaeology.

Since the early 1990s, one can isolate the optical signal of a single molecule and single-molecule spectroscopy has quickly grown into an important research field.

This dissertation explores how we can make anomaly detection—identifying unusual or faulty behavior in complex systems—more trustworthy and effective, with a focus on smart manufacturing.

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…

This thesis is a collection of experimental attempts to enhance photoluminescence of fluorescent molecules and quantum dots with single gold nanorods (GNRs) and relevant applications.

On 14 December, Jouke Tegelaar defended the thesis 'Single supervision, single judicial protection? Towards effective judicial protection in Single Supervisory Mechanism composite procedures'. The doctoral research was supervised by Matthias Haentjens and Willemien den Ouden.

Structural variants (SVs) are the hidden architecture of the human genome, and are critical for us to understand diseases, evolution, and so on.

In this thesis we investigated the ability of two-photon multifocal microscopy for single-molecule microscopy in live cells and organisms.

Single-Molecule Microscopy (SMM) techniques constitute a group of powerful imaging tools that enable researchers to study the dynamic behavior of individual molecules.

In the era of big data, extracting insights from complex datasets is a key challenge. This thesis demonstrates the superiority of graph-based methods over traditional clustering (e.g., k-means, DBSCAN) and outlier detection for analyzing high-dimensional and noisy data.

This dissertation revolves around the design and implementation of novel instrumentation and related measurement techniques, at the single molecule level, for use in biophysical research. Chapter 1 presents an introduction to the field of fluorescence-based single molecule measurements. In particular,…

The sequence-dependence of biomolecular interactions involving nucleic acids and proteins is essential for numerous processes inside the cell. Insights into the underlying molecular mechanisms have been obtained using various biochemical and biophysical methods on two different levels — bulk and sin…

Spectroscopic studies on fluorescent single molecules in organic condensed matter does not only provide information about the molecule itself, but also its near environment. By suppression of phonon-induced broadening of spectral lines through cooling to low temperatures, small changes in the spectral…

Promotor: Prof. dr. I. Snellen, Co-Promotor: Dr. M. Kenworthy

Promotor: E. Bouwman Co-Promotor: S. Bonnet

Curved single crystals provide variable, but well-defined surface structures.

On the 10th of November, Martin Kroon successfully defended a doctoral thesis. The Leiden University Centre for Linguistics congratulates Martin on this achievement!

This thesis aims to improve the detection from ultra-weak single emitter by enhancing their emission properties with plasmonic nanostructures. We exploit the wet-chemically synthesized single crystalline gold nanorods (GNRs) as our basic frameworks in the whole studies, simply because of their unique…

PhD defence

It's pretty hard to spot a single 5 nanometer particle. Leiden physicists pulled it off by turning a 120 nm gold rod into a detector.

Miles Kellerman, Assistant Professor at Leiden University, argues in a new article that governments should consider empowering financial crime bounty hunters by creating Licensed Detection Agents to address structural failures in current systems for detecting financial crime.

Mechanobiology is a major area in biology, however, mechanics is currently a missing element in drug development pipelines. This has led to a high cost for the society. Mechanotoxicity of drugs often appears as a long-term side effect of drugs, and has led to removal of drugs from the market. Furthermore,…

The goal is to reduce single use coffee cup use both at the university cafés and cofee machines.

On 8 January 2020, Jelmer Brouwer defended his thesis 'Detection, detention, deportation'. The doctoral research was supervised by Prof. J.P. van der Leun and Prof. M.A.H. van der Woude.

Intrigued by the way cells autonomously regulate their fate, we strive to understand and visualize cellular processes as the basis of Cell Signaling.

In this thesis, we study different curved single crystals because of the diversity of surface structures across their curvature.

In this thesis, we describe the latest advances in SQUID-detected Magnetic Resonance Force Microscopy (MRFM).

In this work, we investigate the minute circular dichroism effects of single nanoparticles.To this aim, we apply photothermal imaging with a polarization-modulated heating beam.

In this project we develop algorithms to automatically detect a particular type of archaeological sites in satellite images of the Alps.

An Ancient Egyptian System of Workmen’s Identity Marks

Promotor: M.A.G.J. Orrit

This thesis describes the Multi-site All-Sky CAmeRA (MASCARA), which consists of two small robotic telescope designed to detect exoplanets around the brightest stars in the sky.

We study cell-fate decision-making using embryonic stem cells as a model system. Stem cells integrate a large number of cues to direct their development into a great variety of cell types.

Promotor: Prof.dr. T. Schmidt, Co-promotor: Dr. ir. S. J.T. van Noort

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.

Leiden physicists have managed to detect a single molecule called dibenzoterrylene in a new crystal, and found that it is a candidate component for a quantum network. Future quantum computers will need such a network to work together while maintaining their advantages. Publication in ChemPhysChem jo…

The major and ultimate aim of metabolomics is to obtain an answer to a specific biological or clinical question.

Promotor: Prof.dr. M.A.G.J. Orrit

Deepfakes are videos that have been manipulated to replace one person’s likeness with that of another. They can be difficult to distinguish from authentic videos. In our study, we found that people who score high on conspiracy thinking and people who use social media more are better at distinguishing…

Generally the data from remote sensing surveys - the scanning of the earth by satellite or aircraft in order to obtain information about it - is screened manually in archaeology. However, constant monitoring of the earth's surface causes a huge influx of data of high complexity and high quality. To…