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arXiv · 1005.0273

Coherent spin manipulation in an exchange-only qubit

E. A. Laird·J. M. Taylor·D. P. DiVincenzo·C. M. Marcus·M. P. Hanson·A. C. Gossard
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Abstract

Initialization, manipulation, and measurement of a three-spin qubit are demonstrated using a few-electron triple quantum dot, where all operations can be driven by tuning the nearest-neighbor exchange interaction. Multiplexed reflectometry, applied to two nearby charge sensors, allows for qubit readout. Decoherence is found to be consistent with predictions based on gate voltage noise with a uniform power spectrum. The theory of the exchange-only qubit is developed and it is shown that initialization of only two spins suffices for operation. Requirements for full multi-qubit control using only exchange and electrostatic interactions are outlined.

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E. A. Laird, J. M. Taylor, D. P. DiVincenzo, C. M. Marcus, M. P. Hanson, A. C. Gossard. 2010-05-03. Coherent spin manipulation in an exchange-only qubit. https://doi.org/10.1103/physrevb.82.075403

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