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Single qubit measurements with an asymmetric single-electron transistor

S. A. Gurvitz·G. P. Berman
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Abstract

We investigate qubit measurements using a single electron transistor (SET). Applying the Schrödinger equation to the entire system we find that an asymmetric SET is considerably more efficient than a symmetric SET. The asymmetric SET becomes close to an ideal detector in the large asymmetry limit. We also compared the SET detector with a point-contact detector. This comparison allows us to illuminate the relation between information gain in the measurement process and the decoherence generated by these measurement devices.

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S. A. Gurvitz, G. P. Berman. 2005-06-19. Single qubit measurements with an asymmetric single-electron transistor. https://doi.org/10.1103/physrevb.72.073303

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