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Efficient quantum computation within a disordered Heisenberg spin-chain

Chiu Fan Lee·Neil F. Johnson
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Abstract

We show that efficient quantum computation is possible using a disordered Heisenberg spin-chain with `always-on' couplings. Such disorder occurs naturally in nanofabricated systems. Considering a simple chain setup, we show that an arbitrary two-qubit gate can be implemented using just three relaxations of a controlled qubit, which amounts to switching the on-site energy terms at most twenty-one times.

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Chiu Fan Lee, Neil F. Johnson. 2004-09-07. Efficient quantum computation within a disordered Heisenberg spin-chain. https://doi.org/10.1103/physreva.70.052322

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