Suppressed crosstalk between two-junction superconducting qubits with mode-selective exchange coupling

• URL: http://arxiv.org/abs/2105.11495v2
• Date: Mon, 22 Nov 2021 16:46:20 GMT
• Title: Suppressed crosstalk between two-junction superconducting qubits with mode-selective exchange coupling
• Abstract summary: We experimentally demonstrate a superconducting architecture using qubits that comprise of two capacitively-shunted Josephson junctions connected in series. We greatly suppress crosstalk between the data modes while permitting all-microwave two-qubit gates.
• Score: 0.0
• License: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Abstract: Fixed-frequency qubits can suffer from always-on interactions that inhibit independent control. Here, we address this issue by experimentally demonstrating a superconducting architecture using qubits that comprise of two capacitively-shunted Josephson junctions connected in series. Historically known as tunable coupling qubits (TCQs), such two-junction qubits support two modes with distinct frequencies and spatial symmetries. By selectively coupling only one type of mode and using the other as our computational basis, we greatly suppress crosstalk between the data modes while permitting all-microwave two-qubit gates.

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