Multiharmonic fields driven adiabatic quantum pumps in nanowire structures

摘要

A dc current can be pumped through a nanostructure by two out-of-phase ac driving fields. In this approach, we investigate the pumped current properties driven by multiharmonic ac fields in nanowire structures. Considering the first five harmonics, the adiabatically pumping properties driven by approximate square, sawtooth, and triangle-shape ac waves are discussed. It is found that the pumped current varies with the phase difference in a square and sawtooth shape, respectively, under corresponding driven fields. Sinusoidal relation governs in the pump driven by a triangle-shape ac field.