The emission of correlated electrons from surfaces

This work offers a theoretical framework for the treatment of the simultaneous many-electron excitation in solids and surfaces. Starting from the transition operator, an expansion is presented that treats all involved interactions on equal footing. The method is applied to the simultaneous two-orbital excitation and the results are compared with recent experimental findings. It is concluded that such studies provide a useful tool for the investigation of inter-electronic coupling. Received: 23 March 1999 / Accepted: 25 June 1999 / Published online: 23 September 1999