Pekola, J. P. and Averin, D. V. and Kafanov, Sergey and Kemppinen, A. and Lotkhov, S. V. and Maisi, V. F. and Meschke, M. and Mottonen, M. and Pashkin, Yu. A. and Saira, O. -P. and Tsai, J. S. and Zorin, A. B. (2010) Hybrid single-electron turnstile:towards a quantum standard of electric current. In: Precision Electromagnetic Measurements (CPEM), 2010 Conference on. IEEE, Daejeon, p. 88.
Full text not available from this repository.Abstract
First I discuss various candidates of single-electron current pumps for quantum metrology. Then I focus on the hybrid normal-metal-superconductor turnstile in the form of a one-island single-electron transistor with one gate [1-3]. The device demonstrates robust current plateaus at multiple levels of ef at frequency f. I discuss the various error mechanisms, based on our experiments and theoretical considerations. Ultimately the quantization accuracy is expected to be limited by either two-electron tunneling or by Cooper-pair-electron co-tunneling [4]. We predict that it should be possible to achieve the metrological accuracy of 10−8, while maintaining the quantized current on the level of more than 10 pA, just by one turnstile with realistic parameters using aluminium as a superconductor. Recently we have managed to run ten turnstiles in parallel increasing the current level to above 100 pA [5]. Work on suppressing the harmful sub-gap leakage current is in progress with encouraging experimental results.