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DOE OSTI · 1903913

Parametric longitudinal coupling between a high-impedance superconducting resonator and a semiconductor quantum dot singlet-triplet spin qubit

Bøttcher, C. L.·Harvey, S. P.·Fallahi, S.·Gardner, G. C.·Manfra, M. J.·Vool, U.·Bartlett, S. D.·Yacoby, A.
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Abstract

Coupling qubits to a superconducting resonator provides a mechanism to enable long-distance entangling operations in a quantum computer based on spins in semiconducting materials. Here, we demonstrate a controllable spin-photon coupling based on a longitudinal interaction between a spin qubit and a resonator. We show that coupling a singlet-triplet qubit to a high-impedance superconducting resonator can produce the desired longitudinal coupling when the qubit is driven near the resonator’s frequency. We measure the energy splitting of the qubit as a function of the drive amplitude and frequency of a microwave signal applied near the resonator antinode, revealing pronounced effects close to the resonator frequency due to longitudinal coupling. By tuning the amplitude of the drive, we reach a regime with longitudinal coupling exceeding 1 MHz. This mechanism for qubit-resonator coupling represents a stepping stone towards producing high-fidelity two-qubit gates mediated by a superconducting resonator.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

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Bøttcher, C. L., Harvey, S. P., Fallahi, S., Gardner, G. C., Manfra, M. J., Vool, U., Bartlett, S. D., Yacoby, A.. 2022-08-15. Parametric longitudinal coupling between a high-impedance superconducting resonator and a semiconductor quantum dot singlet-triplet spin qubit. https://doi.org/10.1038/s41467-022-32236-w

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