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arXiv · 2501.03578

Four-body coupler for superconducting qubits based on Josephson parametric oscillators

Ryoji Miyazaki·Tsuyoshi Yamamoto
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Abstract

We theoretically propose a circuit of the four-body coupler for superconducting qubits based on Josephson parametric oscillators (JPOs). Our coupler for the four-body interaction has a superconducting loop, similar to a capacitively shunted flux qubit, where an external magnetic flux set to half a flux quantum is threaded. This coupler circuit is a specific setup of the circuit called superconducting nonlinear asymmetric inductive elements (SNAIL) and also is a generalization of the previously proposed one for the four-body interaction of JPOs. We clarify roles of circuit parameters in the four-body interaction and, in particular, show that the four-body coupling constant in our circuit can be significantly increased by tuning capacitance of the coupler or the area ratio of the Josephson junctions of the coupler.

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Ryoji Miyazaki, Tsuyoshi Yamamoto. 2025-04-23. Four-body coupler for superconducting qubits based on Josephson parametric oscillators. https://doi.org/10.1103/physreva.111.062612

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