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arXiv · 1901.05218

Evidence for universality of tunable-barrier electron pumps

Stephen P. Giblin·Akira Fujiwara·Gento Yamahata·Myung-Ho Bae·Nam Kim·Alessandro Rossi·Mikko Möttönen·Masaya Kataoka
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Abstract

We review recent precision measurements on semiconductor tunable-barrier electron pumps operating in a ratchet mode. Seven studies on five different designs of pumps have reported measurements of the pump current with relative total uncertainties around $10^{-6}$ or less. Combined with theoretical models of electron capture by the pumps, these experimental data exhibits encouraging evidence that the pumps operate according to a universal mechanism, independent of the details of device design. Evidence for robustness of the pump current against changes in the control parameters is at a more preliminary stage, but also encouraging, with two studies reporting robustness of the pump current against three or more parameters in the range of $\sim\!5 \times 10^{-7}$ to $\sim\!2 \times 10^{-6}$. This review highlights the need for an agreed protocol for tuning the electron pump for optimal operation, as well as more rigorous evaluations of the robustness in a wide range of pump designs.

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Stephen P. Giblin, Akira Fujiwara, Gento Yamahata, Myung-Ho Bae, Nam Kim, Alessandro Rossi, Mikko Möttönen, Masaya Kataoka. 2019-01-16. Evidence for universality of tunable-barrier electron pumps. https://doi.org/10.1088/1681-7575/ab29a5

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