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arXiv · 1702.03568

Parallel Position-Controlled Composite Quantum Logic Gates with Trapped Ions

Michael S. Gutierrez·Guang Hao Low·Richard Rines·Helena Zhang
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Abstract

We demonstrate parallel composite quantum logic gates with phases implemented locally through nanoscale movement of ions within a global laser beam of fixed pulse duration. We show that a simple four-pulse sequence suffices for constructing ideal arbitrary single-qubit rotations in the presence of large intensity inhomogeneities across the ion trap due to laser beam-pointing or beam-focusing. Using such sequences, we perform parallel arbitrary rotations on ions in two trapping zones separated by 700 $\mu$m with fidelities comparable to those of our standard laser-controlled gates. Our scheme improves on current transport or zone-dependent quantum gates to include phase modulation with local control of the ion's confinement potential. This enables a scalable implementation of an arbitrary number of parallel operations on densely packed qubits with a single laser modulator and beam path.

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Michael S. Gutierrez, Guang Hao Low, Richard Rines, Helena Zhang. 2017-02-12. Parallel Position-Controlled Composite Quantum Logic Gates with Trapped Ions. https://arxiv.org/abs/1702.03568

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