SOLVABLE 3-STATE MODEL OF A DRIVEN DOUBLE-WELL POTENTIAL AND COHERENTDESTRUCTION OF TUNNELING

A simple model for a particle in a double well is derived from discret izing its configuration space. The model contains as many free paramet ers as the original system and it respects all the existing symmetries . In the presence of an external periodic force both the continuous sy stem and the discrete model are shown to possess a generalized time-re versal symmetry in addition to the known generalized parity. The impac t of the driving force on the spectrum of the Floquet operator is stud ied. In particular, the occurrence of degenerate quasienergies causing coherent destruction of tunneling is discussed-to a large extent anal ytically-for arbitrary driving frequencies and barrier heights. [S1050 -2947(98)00301-1].