Generalized coherent states and the uncertainty principle

We derive from a dynamical symmetry property that the linear and nonlinear Schrödinger equations with harmonic potential possess an infinite string of shape-preserving coherent wave-packet states with classical motion. Unlike the Schrödinger state with $\Delta x\Delta p=\frac{\hslash }{2}$, the uncertainty product can be arbitrarily large for these states showing that classical motion is not necessarily linked with minimum uncertainty. We obtain a generalization of Sudarshan's diagonal coherent-state representation in terms of these states.