A fluxonium-based artificial molecule with a tunable magnetic moment

Abstract

Engineered quantum systems allow us to observe phenomena that are not easily accessible naturally. The LEGO-like nature of superconducting circuits makes them particularly suited for building and coupling artificial atoms. Here, we introduce an artificial molecule, composed of two strongly coupled fluxonium atoms, which possesses a tunable magnetic moment. Using an applied external flux, one can tune the molecule between two regimes: one in which the ground-excited state manifold has a magnetic dipole moment and one in which the ground-excited state manifold has only a magnetic quadrupole moment. By varying the applied external flux, we find the coherence of the molecule to be limited by local flux noise. The ability to engineer and control artificial molecules paves the way for building more complex circuits for protected qubits and quantum simulation.

10 pages, 8 figures

References in corpus (9)

• Coupling Superconducting Qubits via a Cavity Bus
• Dynamical decoupling and noise spectroscopy with a superconducting flux qubit
• Decoherence of flux qubits due to 1/f flux noise
• Spectroscopy on two coupled flux qubits
• Implementation of low-loss superinductances for quantum circuits
• Model for l/f Flux Noise in SQUIDs and Qubits
• Origin and Suppression of $1/f$ Magnetic Flux Noise
• Microscopic origin of low frequency flux noise in Josephson circuits
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Cited by in corpus (30)

• The high-coherence fluxonium qubit
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• Moving beyond the transmon: Noise-protected superconducting quantum circuits
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• Scalable High-Performance Fluxonium Quantum Processor
• Aharonov-Bohm Caging and Inverse Anderson transition in Ultracold Atoms
• Bifluxon: Fluxon-Parity-Protected Superconducting Qubit
• Engineering Dynamical Sweet Spots to Protect Qubits from 1/$f$ Noise
• AC flux sweet spots in parametrically-modulated superconducting qubits
• Floquet-engineered enhancement of coherence times in a driven fluxonium qubit
• Driving forbidden transitions in the fluxonium artificial atom
• Fast high-fidelity gates for galvanically-coupled fluxonium qubits using strong flux modulation
• Entangling transmons with low-frequency protected superconducting qubits
• Operating in a deep underground facility improves the locking of gradiometric fluxonium qubits at the sweet spots
• Right-sizing fluxonium against charge noise
• Parity-Engineered Light-Matter Interaction
• Fluxon-Based Quantum Simulation in Circuit QED
• Multi-mode superconducting circuits for realizing strongly coupled multi-qubit processor units
• Two-dimensional network of atomtronic qubits
• The Floquet Fluxonium Molecule: Driving Down Dephasing in Coupled Superconducting Qubits
• Light-dressing of a diatomic superconducting artificial molecule
• Dephasing in Fluxonium Qubits from Coherent Quantum Phase Slips
• Flux-pulse-assisted Readout of a Fluxonium Qubit
• SKIFFS: Superconducting Kinetic Inductance Field-Frequency Sensors for Sensitive Magnetometry in Moderate Background Magnetic Fields
• Characterisation of spatial charge sensitivity in a multi-mode superconducting qubit
• Detector of microwave photon pairs based on a Josephson photomultiplier
• In situ Al${}_2$O${}_3$ passivation of epitaxial tantalum and aluminum films enables long-term stability in superconducting microwave resonators
• Performance-centric roadmap for building a superconducting quantum computer
• Robust multi-mode superconducting circuit optimized for quantum information processing