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arXiv · 0707.3695

Weak values of electron spin in a double quantum dot

Alessandro Romito·Yuval Gefen·Yaroslav M. Blanter
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Abstract

We propose a protocol for a controlled experiment to measure a weak value of the electron's spin in a solid state device. The weak value is obtained by a two step procedure -- weak measurement followed by a strong one (post-selection), where the outcome of the first measurement is kept provided a second post-selected outcome occurs. The set-up consists of a double quantum dot and a weakly coupled quantum point contact to be used as a detector. Anomalously large values of the spin of a two electron system are predicted, as well as negative values of the total spin. We also show how to incorporate the adverse effect of decoherence into this procedure.

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Alessandro Romito, Yuval Gefen, Yaroslav M. Blanter. 2008-03-04. Weak values of electron spin in a double quantum dot. https://doi.org/10.1103/physrevlett.100.056801

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