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Theory of a double-dot charge detector

Tamas Geszti·Jozsef Zsolt Bernad
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Abstract

A double quantum dot charge detector, with one dot Coulomb coupled to the electron to be detected and the other modulated by a time-dependent plunger voltage, is analyzed in a minimal model. The signal and noise of the detector are calculated by a standard master equation and MacDonald formula technique. We find a dip in the noise spectrum at the double Rabi frequency of the double dot, defining the bandwidth available for detecting charges in motion.

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Tamas Geszti, Jozsef Zsolt Bernad. 2008-02-12. Theory of a double-dot charge detector. https://doi.org/10.1103/physrevb.73.235343

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