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arXiv · 1802.01327

Voltage-Controlled Superconducting Quantum Bus

L. Casparis·N. J. Pearson·A. Kringhøj·T. W. Larsen·F. Kuemmeth·J. Nygård·P. Krogstrup·K. D. Petersson·C. M. Marcus
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Abstract

We demonstrate the ability of an epitaxial semiconductor-superconductor nanowire to serve as a field-effect switch to tune a superconducting cavity. Two superconducting gatemon qubits are coupled to the cavity, which acts as a quantum bus. Using a gate voltage to control the superconducting switch yields up to a factor of 8 change in qubit-qubit coupling between the on and off states without detrimental effect on qubit coherence. High-bandwidth operation of the coupling switch on nanosecond timescales degrades qubit coherence.

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L. Casparis, N. J. Pearson, A. Kringhøj, T. W. Larsen, F. Kuemmeth, J. Nygård, P. Krogstrup, K. D. Petersson, C. M. Marcus. 2018-02-05. Voltage-Controlled Superconducting Quantum Bus. https://doi.org/10.1103/physrevb.99.085434

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