Single-electron pumping in single-common-gate triple-dot devices with asymmetric gate capacitances

Abstract

Single-common-gate triple-dot single-electron devices with homogeneous junction capacitances and asymmetric gate capacitances can transfer a single electron to a negative-biased electrode, that is, single-electron pumping can be achieved by alternating only one gate voltage. The device can work as a pump if the gate capacitances have a large–small–small, large–large–small, or large–medium–small distribution with an appropriate large–small difference. The third distribution is preferable because it can take the maximum large–small difference and single-electron pumping is possible with the largest negative-biasing voltage.