Quantum-Assisted Optical Spectroscopy

The QUAOS project is dedicated to the wave-particle duality, a phenomenon that is often referred to as the most characteristic manifestation of the laws of quantum mechanics. It deals with the fact that light as well as matter show properties of waves in some experiments while they appear corpuscular in others. Even larger and more complex molecules, such as the well-known C60 fullerenes, vitamins and peptides show wave properties under certain experimental conditions, in particular diffraction and interference. This phenomenon can also been shown for much larger molecules while the world record as measured in Vienna is at about 10,000 times the mass of a hydrogen atom. While modern experimental quantum mechanics is still searching for answers, such as how the transition from classical to quantum mechanics may be understood, the wave nature of microscopic matter can still be used to extract valuable molecular information. It turns out that wave properties of molecules e.g. their phases are very sensitive to external perturbations. They shift when the molecules interact with light for instance. This effect can now be used to investigate their optical behaviour. Interesting test candidates for this novel spectroscopy method are biologically relevant molecules like vitamins, peptides and small proteins. Their optical behaviour can be considered as kind of a fingerprint of their internal structure and therefore its determination is of great importance for a deeper understanding of fundamental concepts in a variety of relevant biomolecular processes.