Manipulating single electrons with a seven-junction pump

In this paper, the operation of a seven-junction electron pump is presented. To characterize the pump, a single-electron tunneling transistor capacitively coupled to the pump was used. With this device, single electrons were manipulated one at a time. By performing electron pumping at a frequency of 1 MHz, an error rate of (4/spl plusmn/1)/spl times/10/sup -5/ was determined. This preliminary result is a solid milestone on the way to the capacitance standard presently under development at the Swiss Federal Office of Metrology and Accreditation.