Parallelized Single Electron Pumps Based on Gate-Tunable Quantum Dot

In order to increase the output current level, we have fabricated a parallelized pump with two gate-tunable quantum-dot pumps based on GaAs/AlGaAs heterostructure. Each pump device is composed of multiple gates forming a quantum dot whose potential shapes and barrier heights are tunable. At optimally potential-tuned condition, we have confirmed that the parallelized pump could be considered as a single pump and its theoretically estimated accuracy stays almost the same as the single one within the theoretical resolution. Thus we produce I=192 pA at 0.6 GHz with an expected accuracy as low as 10
^-6
level.