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arXiv · 1009.1746

An in-situ tunable radio-frequency quantum point contact

Thomas Müller·Bruno Küng·Paul Studerus·Sarah Hellmüller·Klaus Ensslin·Thomas Ihn·Matthias Reinwald·Werner Wegscheider
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Abstract

Incorporating a variable capacitance diode into a radio-frequency matching circuit allows us to in-situ tune the resonance frequency of an RF quantum point contact, increasing the versatility of the latter as a fast charge sensor of a proximal quantum circuit. The performance of this method is compared in detail to conventional low-frequency charge detection. The approach is also applicable to other RF-detection schemes, such as RF-SET circuits.

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Thomas Müller, Bruno Küng, Paul Studerus, Sarah Hellmüller, Klaus Ensslin, Thomas Ihn, Matthias Reinwald, Werner Wegscheider. 2010-09-14. An in-situ tunable radio-frequency quantum point contact. https://doi.org/10.1063/1.3517483

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