STATIC-FIELD EFFECTS ON THE NONLINEAR QUANTUM RESONANCES AND THE IONIZATION SPECTRUM OF A SIMPLE HOUND PARTICLE

A comparison of nonlinear classical resonances with the nonlinear quan tum resonances has been well established for semiclassical systems. Ho wever, systems in which tunneling is present are no longer semiclassic al and the correspondence between the classical and quantum systems br eaks down. We examine nonlinear quantum resonances in a system consist ing of a triangular potential well (formed by a static field plus an i mpenetrable wall) with an attractive delta-function potential well and a weak external time-periodic force. In this system, tunneling is imp ortant and nonlinear quantum resonances that have no classical counter part can occur. In the second part of this paper, we remove the impene trable wall and consider this system to be a model of a bounded partic le subject to a strong external static held and a weak periodic held. The presence of the static field leads to strong enhancement and suppr ession of the single-photon photodetachment rates for certain frequenc ies. This effect has been observed experimentally in the photodetachme nt of H- ions and predicted by theoretical models. The model present h ere is particularly useful because the photodetachment spectrum can be obtained analytically and leads to greater insight into more realisti c models.