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arXiv · 1101.4784

Quantum-limited charge detection with two quantum point contacts

Kang-Ho Lee·Kicheon Kang
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Abstract

We present a scheme for tuning two quantum point contacts as a quantum-limited charge detector. Based on the scattering matrix approach, we analyze a general condition of quantum-limited detection with a single-channel quantum detector possessing time-reversal symmetry. From this analysis we find that quantum-limited detection can be easily realized with two quantum point contacts connected in series, which is not possible if only a single quantum point contact is used. We also discuss the sensitivity enhancement due to multiple reflections of the two point contacts.

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Kang-Ho Lee, Kicheon Kang. 2011-01-25. Quantum-limited charge detection with two quantum point contacts. https://doi.org/10.1103/physrevb.84.033404

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