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arXiv · 2506.03239

Cavity-mediated cross-cross-resonance gate

Alexey V. Gorshkov·Daniel Cohen·Arbel Haim·Amit Rotem·Or Golan·Gihwan Kim·Andreas Butler·Connor T. Hann·Oskar Painter·Fernando G. S. L. Brandão·Alex Retzker
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Abstract

We propose a cavity-mediated gate between two transmon qubits or other nonlinear superconducting elements. The gate is realized by driving both qubits at a frequency that is near-resonant with the frequency of the cavity. Since both qubits are subject to a cross-resonant drive, we call this gate a cross-cross-resonance gate. In close analogy with gates between trapped-ion qubits, in phase space, the state of the cavity makes a circle whose area depends on the state of the two qubits, realizing a controlled-phase gate. We propose two schemes for canceling the dominant error, which is the dispersive coupling. We also show that this cross-cross-resonance gate allows one to realize simultaneous gates between multiple pairs of qubits coupled via the same metamaterial composed of an array of coupled cavities or other linear mediators.

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Alexey V. Gorshkov, Daniel Cohen, Arbel Haim, Amit Rotem, Or Golan, Gihwan Kim, Andreas Butler, Connor T. Hann, Oskar Painter, Fernando G. S. L. Brandão, Alex Retzker. 2025-06-03. Cavity-mediated cross-cross-resonance gate. https://arxiv.org/abs/2506.03239

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