Major Award for our Colleague at ECAMP Conference

Our Colleague, young researcher Janez Turnšek, received an outstanding poster presentation award for his contribution entitled "Amplification of spontaneous emission from doubly excited He atoms". The ECAMP (European Conference on Atoms Molecules and Photons) is under way in Innsbruck this week.

Janez, together with co-authors, studied self-amplified spontaneous emission (ASE) from helium atoms in a doubly excited state, which typically decays non-radiatively (via autoionization), but occasionally emits an XUV photon. By directing intense, resonantly tuned light pulses from the FERMI free-electron laser through a dense helium gas column, it was possible to amplify this weak fluorescence signal and direct it along the incident light beam, achieving a maximum photon conversion efficiency of 4.1%. At the same time, they recorded visible light emission spectra along the gas cell, emitted by He atoms and ions during transitions between singly excited states. They observed a decrease in intensity with increasing distance from the entrance of the target cell, due to FEL light absorption. Additionally, a weak positive correlation between the visible fluorescence and the XUV ASE signal was detected at the cell’s exit.