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arXiv · 1512.04642

Superadiabatic Control of Quantum Operations

Jonathan Vandermause·Chandrasekhar Ramanathan
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Abstract

Adiabatic pulses are used extensively to enable robust control of quantum operations. We introduce a new approach to adiabatic control that uses the superadiabatic quality or $Q$-factor as a performance metric to design robust, high fidelity pulses. This approach permits the systematic design of quantum control schemes to maximize the adiabaticity of a unitary operation in a particular time interval given the available control resources. The interplay between adiabaticity, fidelity and robustness of the resulting pulses is examined for the case of single-qubit inversion, and superadiabatic pulses are demonstrated to have improved robustness to control errors. A numerical search strategy is developed to find a broader class of adiabatic operations, including multi-qubit adiabatic unitaries. We illustrate the utility of this search strategy by designing control waveforms that adiabatically implement a two-qubit entangling gate for a model NMR system.

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Jonathan Vandermause, Chandrasekhar Ramanathan. 2016-04-20. Superadiabatic Control of Quantum Operations. https://doi.org/10.1103/physreva.93.052329

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