Dynamical study on charge injection and transport in a metal/polythiophene/metal structure

The dynamical process of charge injection from metal electrode to anondegenerate polymer in a metal/polythiophene (PT)/metal structurehas been investigated by using a nonadiabatic dynamic approach. Itis found that the injected charges form wave packets due to thestrong electron-lattice interaction in PT. We demonstrate that thedynamical formation of the wave packet sensitively depends on thestrength of applied voltage, the electric field, and the contactbetween PT and electrode. At a strength of the electric field morethan $3.0times 10^{4}$,V/cm, the carriers can be ejected from thePT into the right electrode. At an electric field more than$3.0times 10^{5}$,V/cm, the wave packet cannot form while it movesrapidly to the right PT/metal interface. It is shown that theejected quantity of charge is noninteger.