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arXiv · 0910.4495

Correcting errors in a quantum gate with pushed ions via optimal control

U. V. Poulsen·S. Sklarz·D. Tannor·T. Calarco
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Abstract

We analyze in detail the so-called "pushing gate" for trapped ions, introducing a time dependent harmonic approximation for the external motion. We show how to extract the average fidelity for the gate from the resulting semi-classical simulations. We characterize and quantify precisely all types of errors coming from the quantum dynamics and reveal for the first time that slight nonlinearities in the ion-pushing force can have a dramatic effect on the adiabaticity of gate operation. By means of quantum optimal control techniques, we show how to suppress each of the resulting gate errors in order to reach a high fidelity compatible with scalable fault-tolerant quantum computing.

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U. V. Poulsen, S. Sklarz, D. Tannor, T. Calarco. 2010-08-18. Correcting errors in a quantum gate with pushed ions via optimal control. https://doi.org/10.1103/physreva.82.012339

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