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

Abstract

Single-common-gate quadruple-dot single-electron devices with asymmetric gate capacitances (C g ) can transfer a single electron to a negativebiased electrode by alternating only one gate voltage. The pumping is possible for non-monotonic C g distributions such as saw-toothed and various random C g distributions, though the C g distributions of the previously reported common-gate triple-dot pumping devices are limited to monotonic ones. The maximum absolute value of negative-biasing voltage against which a single electron can be transferred is 0.2181•e/C j , where e is the elementary charge and C j is the junction capacitance. This is 2.7 times larger than the largest one in common-gate triple-dot pumping devices with a monotonic C g distribution.