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Electron Counting Capacitance Standard with an improved five-junction R-pump



Benedetta Camarota, Hansjoerg Scherer, Sergey Lotkhov, Gerd-Dietmar Willenberg, Franz Josef Ahlers, Mark W. Keller


The Electron Counting Capacitance Standard currently pursued at PTB, aims at the closure of the Quantum Metrological Triangle with a final precision of a few parts in 107. This paper reports the considerable progress recently achieved with a new generation of single-electron tunneling devices. A five-junction R-pump was operated with a relative charge transfer error of five electrons in 107, and was used to successfully perform single-electron charging of a cryogenic capacitor. The preliminary result for the single-electron charge quantum has an uncertainty of less than two parts in 106 and is consistent with the value of the elementary charge.


single-electron tunneling, quantum metrology triangle, capacitance standard


Camarota, B. , Scherer, H. , Lotkhov, S. , Willenberg, G. , Ahlers, F. and Keller, M. (2011), Electron Counting Capacitance Standard with an improved five-junction R-pump, Metrologia, [online], (Accessed April 15, 2024)
Created November 6, 2011, Updated October 12, 2021