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arXiv · 1909.02091

Tunable three-body coupler for superconducting flux qubits

Denis Melanson·Antonio J. Martinez·Salil Bedkihal·Adrian Lupascu
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Abstract

The implementation of many-body interactions is relevant in various areas of quantum information. We present a superconducting device that implements a strong and tunable three-body interaction between superconducting quantum bits, with vanishing two-body interactions and robustness against noise and circuit parameter variations. These properties are confirmed by calculations based on the Born-Oppenheimer approximation, a two-level model for the coupling circuit, and numerical diagonalization. This circuit behaves as an ideal computational basis ZZZ coupler in a simulated three-qubit quantum annealing experiment. This work will be relevant for advanced quantum annealing protocols and future developments of high-order many-body interactions in quantum computers and simulators.

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Denis Melanson, Antonio J. Martinez, Salil Bedkihal, Adrian Lupascu. 2019-09-04. Tunable three-body coupler for superconducting flux qubits. https://arxiv.org/abs/1909.02091

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