An in situ tunable radio-frequency quantum point contact
T. Müller, Bruno Küng, S. Hellmüller +5 more
Incorporating a variable capacitance diode into a radio-frequency (rf) matching circuit allows us to in situ tune the resonance frequency of a 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 single electron transistor circuits.
arXiv:1009.1746•Applied Physics Letters•Nov 15, 2010•27 citations