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arXiv · 1410.5641

The NV center as a quantum actuator: time-optimal control of nuclear spins

Clarice D. Aiello·Paola Cappellaro
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Abstract

Indirect control of qubits by a quantum actuator has been proposed as an appealing strategy to manipulate qubits that couple only weakly to external fields. While universal quantum control can be easily achieved when the actuator-qubit coupling is anisotropic, the efficiency of this approach is less clear. Here we analyze the time-efficiency of the quantum actuator control. We describe a strategy to find time-optimal control sequence by the quantum actuator and compare their gate times with direct driving, identifying regimes where the actuator control performs faster. As an example, we focus on a specific implementation based on the Nitrogen-Vacancy center electronic spin in diamond (the actuator) and nearby carbon-13 nuclear spins (the qubits).

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Clarice D. Aiello, Paola Cappellaro. 2014-10-21. The NV center as a quantum actuator: time-optimal control of nuclear spins. https://doi.org/10.1103/physreva.91.042340

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