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arXiv · 2406.14967

Magnon-mediated quantum gates for superconducting qubits

Martijn Dols·Sanchar Sharma·Lenos Bechara·Yaroslav M. Blanter·Marios Kounalakis·Silvia Viola Kusminskiy
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Abstract

We propose a hybrid quantum system consisting of a magnetic particle inductively coupled to two superconducting transmon qubits, where qubit-qubit interactions are mediated via magnons. We show that the system can be tuned into three different regimes of effective qubit-qubit interactions, namely a transverse ($XX + YY$), a longitudinal ($ZZ$) and a non-trivial $ZX$ interaction. In addition, we show that an enhanced coupling can be achieved by employing an ellipsoidal magnet, carrying anisotropic magnetic fluctuations. We propose a scheme for realizing two-qubit gates, and simulate their performance under realistic experimental conditions. We find that iSWAP and CZ gates can be performed in this setup with an average fidelity $\gtrsim 99 \% $ , while an iCNOT gate can be applied with an average fidelity $\gtrsim 88 \%$. Our proposed hybrid circuit architecture offers an alternative platform for realizing two-qubit gates between superconducting qubits and could be employed for constructing qubit networks using magnons as mediators.

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Martijn Dols, Sanchar Sharma, Lenos Bechara, Yaroslav M. Blanter, Marios Kounalakis, Silvia Viola Kusminskiy. 2024-06-21. Magnon-mediated quantum gates for superconducting qubits. https://doi.org/10.1103/physrevb.110.104416

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