Demonstrating a long-coherence dual-rail erasure qubit using tunable transmons

Abstract

Quantum error correction with erasure qubits promises significant advantages over standard error correction due to favorable thresholds for erasure errors. To realize this advantage in practice requires a qubit for which nearly all errors are such erasure errors, and the ability to check for erasure errors without dephasing the qubit. We demonstrate that a "dual-rail qubit" consisting of a pair of resonantly coupled transmons can form a highly coherent erasure qubit, where transmon $T_1$ errors are converted into erasure errors and residual dephasing is strongly suppressed, leading to millisecond-scale coherence within the qubit subspace. We show that single-qubit gates are limited primarily by erasure errors, with erasure probability $p_{\text{erasure}}=2.19(2)\times 10^{-3}$ per gate while the residual errors are $\sim 40$ times lower. We further demonstrate mid-circuit detection of erasure errors while introducing $<0.1\%$ dephasing error per check. Finally, we show that the suppression of transmon noise allows this dual-rail qubit to preserve high coherence over a broad tunable operating range, offering an improved capacity to avoid frequency collisions. This work establishes transmon-based dual-rail qubits as an attractive building block for hardware-efficient quantum error correction.

9+13 pages, 16 figures

References in corpus (41)

• A Quantum Engineer's Guide to Superconducting Qubits
• Introduction to Quantum Noise, Measurement and Amplification
• Suppressing quantum errors by scaling a surface code logical qubit
• Dynamical decoupling and noise spectroscopy with a superconducting flux qubit
• Efficient Z-Gates for Quantum Computing
• High-fidelity parallel entangling gates on a neutral atom quantum computer
• A Simple Quantum Computer
• Real-time quantum error correction beyond break-even
• Codes for the Quantum Erasure Channel
• Building a fault-tolerant quantum computer using concatenated cat codes
• Rapid high-fidelity multiplexed readout of superconducting qubits
• Quantum Gates and Memory using Microwave Dressed States
• Dynamically Error-Corrected Gates for Universal Quantum Computation
• Error-mitigated digital quantum simulation
• Exponential suppression of bit-flips in a qubit encoded in an oscillator
• High-fidelity gates with mid-circuit erasure conversion in a metastable neutral atom qubit
• Erasure conversion for fault-tolerant quantum computing in alkaline earth Rydberg atom arrays
• Measurement-induced state transitions in a superconducting qubit: Beyond the rotating wave approximation
• Feedback control of a solid-state qubit using high-fidelity projective measurement
• Repetition Cat Qubits for Fault-Tolerant Quantum Computation
• High-Fidelity Bell-State Preparation with ${}^{40}$Ca${}^{+}$ Optical Qubits
• Erasure conversion in a high-fidelity Rydberg quantum simulator
• Reduced phase error through optimized control of a superconducting qubit
• Quantum superposition of a single microwave photon in two different "colour" states
• Removing leakage-induced correlated errors in superconducting quantum error correction
• Tailoring surface codes for highly biased noise
• Universal coherence protection in a solid-state spin qubit
• Experimental demonstration of continuous quantum error correction
• Quantum Error Correction with Metastable States of Trapped Ions Using Erasure Conversion
• Measurement-Induced State Transitions in a Superconducting Qubit: Within the Rotating Wave Approximation
• Erasure qubits: Overcoming the $T_1$ limit in superconducting circuits
• High threshold codes for neutral atom qubits with biased erasure errors
• Dual-rail encoding with superconducting cavities
• Tomography via Correlation of Noisy Measurement Records
• Engineering Dynamical Sweet Spots to Protect Qubits from 1/$f$ Noise
• All-microwave leakage reduction units for quantum error correction with superconducting transmon qubits
• Universal non-adiabatic control of small-gap superconducting qubits
• Experimental demonstration of cheap and accurate phase estimation
• Semiconductor-inspired design principles for superconducting quantum computing
• Fast high-fidelity gates for galvanically-coupled fluxonium qubits using strong flux modulation
• Certified quantum gates

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• Recovering Quantum Coherence of a Cavity Qubit Coupled to a Noisy Ancilla through Real-Time Feedback
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• Synthetic $\pi$-flux system in 2D superconducting qubit array with tunable coupling
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• Doubling Qubits in a Trapped-Ion System via Vibrational Dual-Rail Encoding
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