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arXiv · 1306.1013

Tomography of a spin qubit in a double quantum dot

Maki Takahashi·Stephen D. Bartlett·Andrew C. Doherty
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Abstract

We investigate a range of methods to perform tomography in a solid-state qubit device, for which a priori initialization and measurement of the qubit is restricted to a single basis of the Bloch sphere. We explore and compare several methods to acquire precise descriptions of additional states and measurements, quantifying both stochastic and systematic errors, ultimately leading to a tomographically-complete set that can be subsequently used in process tomography. We focus in detail on the example of a spin qubit formed by the singlet-triplet subspace of two electron spins in a GaAs double quantum dot, although our approach is quite general.

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Maki Takahashi, Stephen D. Bartlett, Andrew C. Doherty. 2013-08-24. Tomography of a spin qubit in a double quantum dot. https://doi.org/10.1103/physreva.88.022120

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