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arXiv · 2309.11287

Three-qubit Parity Gate via Simultaneous Cross Resonance Drives

Toshinari Itoko·Moein Malekakhlagh·Naoki Kanazawa·Maika Takita
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Abstract

Native multi-qubit parity gates have various potential quantum computing applications, such as entanglement creation, logical state encoding and parity measurement in quantum error correction. Here, using simultaneous cross-resonance drives on two control qubits with a common target, we demonstrate an efficient implementation of a three-qubit parity gate. We have developed a calibration procedure based on the one for the echoed cross-resonance gate. We confirm that our use of simultaneous drives leads to higher interleaved randomized benchmarking fidelities than a naive implementation with two consecutive CNOT gates. We also demonstrate that our simultaneous parity gates can significantly improve the parity measurement error probability for the heavy-hexagon code on an IBM Quantum processor using seven superconducting qubits with all-microwave control.

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Toshinari Itoko, Moein Malekakhlagh, Naoki Kanazawa, Maika Takita. 2023-09-20. Three-qubit Parity Gate via Simultaneous Cross Resonance Drives. https://arxiv.org/abs/2309.11287

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