Isolated Strong Optical Magnetic Pulse Spectroscopy

Spectroscopy is the study of the interactions of electro-magnetic radiation (EMR) with matter. At the macroscopic level it can reveal the content of gaseous, liquid, crystalline, and amorphous materials, as well as their density, temperature, and structure. Spectroscopy also allows looking at the properties of isolated molecules and atoms, seeing how they are constructed, and how they interact with each other. This makes spectroscopy an important junction of fundamental chemistry and physics with practical applications, ranging from the development of new materials to analysis of historical heritage and the atmosphere of exoplanets. There are many types of spectroscopy, because EMR is a very diverse term that includes radio waves, micro waves, as well as light and X-ray radiation. Light in its turn is much broader concept than you might think: it can be visible and perceivable by human eye, but a much larger fraction of light stays invisible for us, as THz-radiation, infrared and UV light. EMR interacts with matter in different ways it can be absorbed, emitted, reflected, diffracted, or scattered. The absorption results in reduction of light after it passed through the sample, however this reduction is not equal for different colors (spectral components) and depends on the material properties. The spectral components absorbed by materials are defined by so-called selection rules, that determine light-matter interactions at molecular, atomic, and nuclear levels. In the iStOMPS project, we want to establish a new form of spectroscopy based on magnetic interac- tions. Light, as any EMR, consists of an oscillating electric field and an oscillating magnetic field. Both are important for the existence of light, but typically the electric field component has a hundred times stronger effect on matter. Therefore, most spectroscopic techniques rely on the electric component only and consequently have to follow the electric selection rules. We want to look for the small effects of the magnetic field component of light on matter, because that follows different, complementary selection rules. It allows observing molecules or particular states of molecules that is hidden from conventional spectroscopy. However, since the magnetic field signal is normally outshone by the much stronger elec- tric field signal, one of our main goals is to develop experimental setups that separate electric and mag- netic fields in space (by about 100 nanometer or one percent of the width of a hair), so that the magnetic field signals can be measured undisturbedly. The other goal is to develop theoretical approaches to sim- ulate and predict what happens in molecules under the influence of the fast and strong magnetic fields involved in the experiments. iStOMPS is a team of scientists from the University of Vienna and the TU Wien, aiming to establish a new form of spectroscopy, based on the magnetic field component of light, by means of photonics and theoretical chemistry.