arXiv:quant-ph/0404163 · Physical Review A

Efficient quantum computation within a disordered Heisenberg spin chain

Chiu Fan Lee, Neil F. Johnson

Published Nov 22, 2004• 13 citations

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 21 times.

DOI: 10.1103/physreva.70.052322

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