University of Leiden - Single Molecule Optics

For many years, the group's research theme has been the resonant interaction of electromagnetic waves, or photons, with condensed matter, consisting in most cases of organic molecules. Photons can be simply absorbed by matter, they can flip spins in a magnetic field in Electron Paramagnetic Resonance (EPR), or excite the electron cloud in optical absorption experiments. However, many of the effects they look at are more complex, nonlinear. They study, for example, the effect of two frequencies on spin echoes in EPR, the emission of light at wavelengths different from that of the excitation laser (fluorescence), and the effect of spin resonance on this emission (optically detected magnetic resonance, ODMR), or phenomena involving two or more photons, such as spectral hole-burning.