Abstract
In this communication, we use the pseudo entropy as a measure of information content of ionic state due to ion-laser interaction in a single trapped ion. We examine numerically the population inversion, and the entropy for the system. Minima for the degree of entanglement occur during the transition from maxima to minima (and vice-versa) for the atomic inversion. Successive peaks show a lowering of the local maximum point indicating a dissipative irreversible change in the ionic state. The results show that, the decoherence effect yields loss of information. The general conclusions reached are illustrated by numerical results.