Coherent Excitation of H(n=2) in Few-Electron Collision Systems

Abstract

Excitation processes in simply-structured one- and two-electron systems are both of fundamental importance and of practical relevance for a number of fields. Valuable information about the dynamics of such collisions can be extracted from a measurement of so-called coherence parameters. These parameters relate to the population of energetically degenerate states and are sensitive to the relative phases between the corresponding excitation amplitudes. In collisions involving hydrogenic atoms, not only the coherence between the energetically degenerate magnetic substates (magnetic quantum number m) but also between the near-degenerate angular momentum states (angular momentum quantum number l) with the same principle quantum number n becomes accessible1.