Electron transport in the Aharonov-Bohm pump

Abstract

A connected nanometer-scale double-ring with leads, which is threaded by both static and oscillating magnetic fields, is suggested as an electron pump. We call this an Aharonov-Bohm pump. The oscillating magnetic fields threading each ring separately with different phase induce a current in one direction. In this system, however, electron pumping does not occur without accompanying static fields that yield persistent current in each ring. Therefore, the persistent current plays the role of potential barrier in the double-barrier pumping system already studied. The strength of the pumping current is varied by changing external parameters, such as the static or the dynamic field, the oscillating frequency, and the amount of phase difference.