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arXiv · 0905.4070

Computation on Spin Chains with Limited Access

Alastair Kay·Peter J. Pemberton-Ross
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Abstract

We show how to implement quantum computation on a system with an intrinsic Hamiltonian by controlling a limited subset of spins. Our primary result is an efficient control sequence on a nearest-neighbor XY spin chain through control of a single site and its interaction with its neighbor. Control of an array of sites yields sufficient parallelism for the implementation of fault-tolerant circuits. The framework exposes contradictions between the control theoretic concept of controllability with the ability of a system to perform quantum computation.

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Alastair Kay, Peter J. Pemberton-Ross. 2009-05-25. Computation on Spin Chains with Limited Access. https://doi.org/10.1103/physreva.81.010301

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