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Proper magnetic fields for nonadiabatic geometric quantum gates in NMR

Kazuto Oshima·Koji Azuma
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Abstract

In a scheme of nonadiabatic purely geometric quantum gates in nuclear magnetic resonance(NMR) systems we propose proper magnitudes of magnetic fields that are suitable for an experiment. We impose a natural condition and reduce the degree of freedom of the magnetic fields to the extent. By varying the magnetic fields with essentially one-dimensional degree of freedom, any spin state can acquire arbitrary purely geometric phase ϕ_{g}=-2π(1-cos{theta}), 0 < cosθ < 1. This is an essential ingredient for constructing universal geometric quantum gates.

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Kazuto Oshima, Koji Azuma. 2003-05-20. Proper magnetic fields for nonadiabatic geometric quantum gates in NMR. https://doi.org/10.1103/physreva.68.034304

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