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arXiv · 1009.6189

Keeping a Single Qubit Alive by Experimental Dynamic Decoupling

David J. Szwer·Simon C. Webster·Andrew M. Steane·David M. Lucas
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Abstract

We demonstrate the use of dynamic decoupling techniques to extend the coherence time of a single memory qubit by nearly two orders of magnitude. By extending the Hahn spin-echo technique to correct for unknown, arbitrary polynomial variations in the qubit precession frequency, we show analytically that the required sequence of pi-pulses is identical to the Uhrig dynamic decoupling (UDD) sequence. We compare UDD and CPMG sequences applied to a single Ca-43 trapped-ion qubit and find that they afford comparable protection in our ambient noise environment.

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David J. Szwer, Simon C. Webster, Andrew M. Steane, David M. Lucas. 2010-09-30. Keeping a Single Qubit Alive by Experimental Dynamic Decoupling. https://doi.org/10.1088/0953-4075/44/2/025501

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