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Two spin measurements in exchange interaction quantum computers

S. D. Barrett·T. M. Stace
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Abstract

We propose and analyse a method for single shot measurement of the total spin of a two electron system in a coupled quantum dot or donor impurity structure, which can be used for readout in a quantum computer. The spin can be inferred by observing spin dependent fluctuations of charge between the two sites, via a nearby electrometer. Realistic experimental parameters indicate that the fidelity of the measurement can be larger than 0.9999 with existing or near-future technology.

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S. D. Barrett, T. M. Stace. 2004-11-23. Two spin measurements in exchange interaction quantum computers. https://arxiv.org/abs/cond-mat/0411581

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