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arXiv · 1210.4645

Dispersive Readout of a Few-Electron Double Quantum Dot with Fast rf Gate-Sensors

J. I. Colless·A. C. Mahoney·J. M. Hornibrook·A. C. Doherty·D. J. Reilly·H. Lu·A. C. Gossard
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Abstract

We report the dispersive charge-state readout of a double quantum dot in the few-electron regime using the in situ gate electrodes as sensitive detectors. We benchmark this gate-sensing technique against the well established quantum point contact (QPC) charge detector and find comparable performance with a bandwidth of 10 MHz and an equivalent charge sensitivity of 6.3 x 10-3 e/ \sqrt Hz. Dispersive gate-sensing alleviates the burden of separate charge detectors for quantum dot systems and promises to enable readout of qubits in scaled-up arrays.

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J. I. Colless, A. C. Mahoney, J. M. Hornibrook, A. C. Doherty, D. J. Reilly, H. Lu, A. C. Gossard. 2012-10-17. Dispersive Readout of a Few-Electron Double Quantum Dot with Fast rf Gate-Sensors. https://doi.org/10.1103/physrevlett.110.046805

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