Flux-Trapping Fluxonium Qubit

Abstract

In pursuit of superconducting quantum computing, fluxonium qubits have recently garnered attention for their large anharmonicity and high coherence at the sweet spot. Towards the large-scale integration of fluxonium qubits, a major obstacle is the need for precise external magnetic flux bias: To achieve high performance at its sweet spot, each qubit requires a DC bias line. However, such lines inductively coupled to the qubits bring in additional wiring overhead, crosstalk, heating, and decoherence, necessitating measures for mitigating the problems. In this work, we propose a flux-trapping fluxonium qubit, which, by leveraging fluxoid quantization, enables the optimal phase biasing without using external magnetic flux control at the operating temperature. We introduce the design and working principle, and demonstrate the phase biasing achieved through fluxoid quantization.

10 pages, 8 figures

References in corpus (24)

• Charge insensitive qubit design derived from the Cooper pair box
• Coupling of two superconductors through a ferromagnet : evidence for a pi-junction
• Suppressing quantum errors by scaling a surface code logical qubit
• Fluxonium: single Cooper pair circuit free of charge offsets
• Quiet SDS Josephson Junctions for Quantum Computing
• Transmon qubit with relaxation time exceeding 0.5 milliseconds
• Laser-annealing Josephson junctions for yielding scaled-up superconducting quantum processors
• 1/f Flux Noise in Josephson Phase Qubits
• Decoherence in Josephson-junction qubits due to critical current fluctuations
• Magnetism in SQUIDs at Millikelvin Temperatures
• Fluxonium: an alternative qubit platform for high-fidelity operations
• High-Fidelity, Frequency-Flexible Two-Qubit Fluxonium Gates with a Transmon Coupler
• Universal fast flux control of a coherent, low-frequency qubit
• Characterizing and optimizing qubit coherence based on SQUID geometry
• Scalable High-Performance Fluxonium Quantum Processor
• Simple Phase Bias for Superconducting Circuits
• Methods for Measuring Magnetic Flux Crosstalk Between Tunable Transmons
• Gradiometric flux qubits with tunable gap
• Operating in a deep underground facility improves the locking of gradiometric fluxonium qubits at the sweet spots
• Superconducting flux qubit with ferromagnetic Josephson $\pi$-junction operating at zero magnetic field
• Learning-based Calibration of Flux Crosstalk in Transmon Qubit Arrays
• High coherence fluxonium manufactured with a wafer-scale uniformity process
• Cross-talk in superconducting qubit lattices with tunable couplers -- comparing transmon and fluxonium architectures
• Non-demolition fluorescence readout and high-fidelity unconditional reset of a fluxonium qubit via dissipation engineering