Physics, mathematics, and technology

2011 Issue №4

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Estimation of errors of detecting the condition of a u bitqubit



In this paper we study the back-action of the quantum point contacton the state of a double quantum dot during the measurement process. To describe this action we introduce an auxiliary subsystem, which is in the entangled states with the original system. This model allowed us to estimate establishment of the steady state of the combined system «double quantum dot — quantum point contact», and identify it as a measurement time and estimate the errors of the qubit states detection.


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