The switching ability of a three-level tight-binding system: The isolated and embedded case

The control of the dynamics of a tight-binding isolated three-level system prepared in a non-stationary initial state is studied as a function of its two control parameters: Alpha a-1, the ratio of the coupling to the energy difference between the initial, the target and the intermediate state, and beta alpha -1, the asymmetry parameter of the coupling between these states. When the system is embedded in a periodic chain, alpha a-1 and beta alpha -1 control the low-voltage conductance G of the whole system. The control law of the average transmission coefficient Teff (with G=Teff(1-Teff)-1) is found to be the same as the control law of the minimum distance between the initial and the target state in the isolated case. The control abilities of alpha a-1 and beta alpha -1 are analytically studied and optimised in the isolated and embedded case. © 1988 IOP Publishing Ltd.