arXiv:cond-mat/0408051 · Physical Review B

Single qubit measurements with an asymmetric single-electron transistor

S. A. Gurvitz, G. P. Berman

Published Aug 3, 2005• 45 citations

Abstract

We investigate qubit measurements using a single-electron transistor (SET). Applying the Schr\"odinger equation to the entire system we find that an asymmetric SET is considerably more efficient than a symmetric SET. Yet, its efficiency does not reach that of an ideal detector even in the large asymmetry limit. We also compare 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.

DOI: 10.1103/physrevb.72.073303

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