First steps toward a quantum capacitance standard at METAS

In the fifth framework program of the European Commission, several metrology institutes have teamed up in a project (COUNT) aiming at the realization of a primary standard of capacitance based on single electron resistive pumps. In this paper, we report the first steps toward the realization of such a standard at the Swiss Federal Office of Metrology and Accreditation (METAS). The measurement setup is described and a stability diagram of a three-junction electron pump measured at an electronic temperature smaller than 100 mK is shown. Pumping experiments were performed at frequencies up to 5 MHz and the corresponding current plateaus (on the pA level) were measured. These preliminary results are promising for the future of the experiment.