Mapping of time-dependent electron orbital alignment

Abstract

Using time-resolved photoelectron imaging, a time-dependent electron orbital alignment is observed during the recurrences of a Rydberg rotational wave packet in krypton. The time-dependent alignment is created via excitation of two ac-Stark shifted states (5d′[5/2]3 and 8d[1/2]1) using a three-photon femtosecond pulse excitation. A straightforward analysis of the measured photoelectron distributions using angular momentum algebra shows that the observed periodic change in the electron orbital alignment is accompanied by a time-dependent change of the associated Bell states. These Bell states describe the entangled system of excited electron and ionic core. Hence, these experiments present a relatively simple excitation scheme for creating a decoherence-free entangled superposition.