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arXiv · 0708.0764

Experimental quantum state tomography of a solid state qubit

L. Rippe·B. Julsgaard·A. Walther·Yan Ying·S. Kröll
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Abstract

Full quantum state tomography is used to characterize the state of an ensemble based qubit implemented through two hyperfine levels in Pr3+ ions, doped into a Y2SiO5 crystal. We experimentally verify that single-qubit rotation errors due to inhomogeneities of the ensemble can be suppressed using the Roos-Moelmer dark state scheme. Fidelities above >90%, presumably limited by excited state decoherence, were achieved. Although not explicitly taken care of in the Roos-Moelmer scheme, it appears that also decoherence due to inhomogeneous broadening on the hyperfine transition is largely suppressed.

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L. Rippe, B. Julsgaard, A. Walther, Yan Ying, S. Kröll. 2007-08-06. Experimental quantum state tomography of a solid state qubit. https://doi.org/10.1103/physreva.77.022307

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