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arXiv · 0903.2295

Composite pulses in NMR as non-adiabatic geometric quantum gates

Yukihiro Ota·Yasusi Kondo
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Abstract

We show that some composite pulses widely employed in NMR experiments are regarded as non-adiabatic geometric quantum gates with Aharanov-Anandan phases. Thus, we reveal the presence of a fundamental issue on quantum mechanics behind the traditional technique of the composite pulses. To examine the robustness of such composite pulses against fluctuations, we present a practical noise model in a two-level system. Then, we find that the composite pulses possesses purely geometrical nature even under a specific type of fluctuations.

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Yukihiro Ota, Yasusi Kondo. 2009-08-07. Composite pulses in NMR as non-adiabatic geometric quantum gates. https://doi.org/10.1103/physreva.80.024302

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