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arXiv · 2410.10416

Complementing the transmon by integrating a geometric shunt inductor

Simone D. Fasciati·Boris Shteynas·Giulio Campanaro·Mustafa Bakr·Shuxiang Cao·Vivek Chidambaram·James Wills·Peter J. Leek
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Abstract

We realize a single-Josephson-junction transmon qubit shunted by a simple geometric inductor. We couple it capacitively to a conventional transmon and show that the ZZ interaction between the two qubits is completely suppressed when they are flux-biased to have opposite-sign anharmonicities. Away from the flux sweet spot of the inductively-shunted transmon, we demonstrate fast two-qubit interactions using first-order sideband transitions. The simplicity of this two-qubit-species circuit makes it promising for building large lattices of superconducting qubits with low coherent error and a rich gate set.

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Simone D. Fasciati, Boris Shteynas, Giulio Campanaro, Mustafa Bakr, Shuxiang Cao, Vivek Chidambaram, James Wills, Peter J. Leek. 2024-10-14. Complementing the transmon by integrating a geometric shunt inductor. https://arxiv.org/abs/2410.10416

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