Formation and Decay of Correlated Quantum States in the Regime of Frequent Collisions Between Atoms

Between October 9th and 17th, the colleagues from our department, Dr Matjaž Žitnik, Dr Andrej Mihelič, Janez Turnšek and Dr. Klemen Bučar, together with the French researcher Dr F. Penent from the Paris Sorbonne University, participated in an experiment at the Gasphase beamline of the Elettra synchrotron. During the experiment, the fluorescence decay of singly and doubly excited electronic states of helium was observed at a controlled gas pressure between 10 and 120 mbar.

For a series of such experiments, a glass gas cell was built in cooperation with the Milan Polytechnic. It separates the gas from the vacuum environment of the synchrotron with two collinear openings of 100 micrometers in size, while at the same time allowing the unhindered passage of the excitation synchrotron beam. The research will contribute to a better understanding of the formation and decay of correlated quantum states in the regime of frequent collisions between atoms.