The frequency-locked turnstile device for single electrons

Abstract

We discuss the operation of an array of ultrasmall metal-oxide-metal tunnel junctions, the single-electron turnstile, which was the first in a class of devices which offer controlled transport of single charge carriers. An alternating voltage of frequency f is used to transfer electrons through the device at a rate of one (or an integer) per cycle. This results in a current I = ef (or a multiple). The operation relies on Coulomb blockade of electron tunneling. The accuracy of the device is affected by thermally enhanced tunneling and by co-tunneling events.