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arXiv:cond-mat/0207457

Gate errors in solid state quantum computation

Xuedong Hu, S. Das Sarma

Published Jul 18, 2002• 2 citations
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Abstract

We review our work on the interplay between non-resonant gates and solid state environment in various solid state quantum computer architectures and the resulting gate errors. Particular, we show that adiabatic condition can be satisfied in small quantum dots, while higher energy excited states can play important role in the evolution of a Cooper-pair-box based quantum computer model. We also show that complicated bandstructure such as that of Si can pose a severe gate control problem.

DOI
10.48550/arxiv.cond-mat/0207457

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In this paper we investigate the effect of dephasing on proposed quantum gates for the solid-state Kane quantum computing architecture. Using a simple model of the decoherence, we find that the typical error in a controlled-NOT gate is $8.3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$. We also compute the fidelities of ZZZ, XXX, swap, and controlled ZZZ operations under a variety of dephasing rates. We show that these numerical results are comparable with the error threshold required for fault tolerant quantum computation.
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