Semiconductor-based quantum dot single-electron pumps are currently the mostpromising candidates for the direct realization of the emerging quantumstandard of the ampere in the International System of Units. Here, we discuss asilicon quantum dot single-electron pump with radio frequency control over thetransparencies of entrance and exit barriers as well as the dot potential. Weshow that our driving protocol leads to robust bidirectional pumping: one canconveniently reverse the direction of the quantized current by changing onlythe phase shift of one driving waveform with respect to the others. We alsostudy the improvement in the robustness of the current quantization owing tothe introduction of three control voltages in comparison with the two-waveformdriving. We anticipate that this pumping technique may be used in the future toperform error counting experiments by pumping the electrons into and out of areservoir island monitored by a charge sensor.
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