Abstract

We shall consider two slit interference experiments involving excited atoms. Since an atom has internal degrees of freedom, the photon produced by spontaneous decay of the atom can provide which path information thereby washing out the fringes. Recently Scully, Englert and Walther^[1] have considered an experiment with micromaser cavities in front of the slits to do this. They argue that the loss of interference is not attributable to any momentum kick or random phase but due exclusively to the orthogonality of the environment states interracting with the atomic paths. We shall argue via a series of examples that the physical interpretation of the cause of the loss of interference depends upon the way in which we choose to describe the environment and that the acquisition of a random phase always remains a valid alternative interpretation.^[2]

© 1992 IQEC