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arXiv · 2512.24992

Mathieu Control of the Effective Coupling in Superconducting Qubits

Yi-Han Yu·Xin-Yi Li·Kai Xu·Heng Fan
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Abstract

A common challenge in superconducting quantum circuits is the trade-off between strong coupling and computational subspace integrity. We present Mathieu control, which uses a non-resonant two-photon drive to create a selective nonlinear frequency shift. This shift modifies interactions while preserving qubit states, enabling continuous tuning of the ZZ coupling, including full suppression, and integrating single- and two-qubit gates with low leakage. For a qubit-coupler-qubit device, it allows independent ZZ control, facilitating a programmable Heisenberg (XXZ) Hamiltonian. Extended to a five-qubit chain, the system can be reconfigured to simulate dynamics of quantum magnetic phases. Mathieu control thus provides a framework for high-fidelity quantum logic and programmable simulation.

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Yi-Han Yu, Xin-Yi Li, Kai Xu, Heng Fan. 2025-12-31. Mathieu Control of the Effective Coupling in Superconducting Qubits. https://arxiv.org/abs/2512.24992

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