SEMIQUANTUM CHAOS IN THE DOUBLE-WELL

The phenomenon of semiquantum chaos is analyzed in a classically regul ar double-well oscillator model. Here it arises from a doubling of the number of effectively classical degrees of freedom, which ark nonline arly coupled in a Gaussian variational approximation (TDHF) to full qu antum mechanics. The resulting first-order nondissipative autonomous f low system shows energy dependent transitions between regular behavior and semiquantum chaos, which we monitor by Poincare sections and a su itable frequency correlation function related to the density matrix. W e discuss the general importance of this form of deterministic chaos a nd point out the necessity to study open (dissipative) quantum systems , in order to observe it experimentally.