Fluxonium
superconducting qubit architecture
In quantum computing, the fluxonium is a type of superconducting qubit architecture used for gate-based quantum computation that is insensitive to offset charge noise. It is constructed from a Josephson junction, a capacitor, and a “superinductor” (a type of inductor) arranged in a loop.
The fluxonium was first proposed as a candidate for a qubit by an experimental group at Yale University led by Michel Devoret in 2009. It is a flux-like qubit, meaning that its energy levels correspond to integer numbers of magnetic flux/phase states. This architecture has long coherence times and high anharmonicity (or nonlinearity), both of which are important for successful qubit architectures. By changing the relative values of the different circuit components, fluxoniums can be engineered to have other properties, such as resistance to noise. However, the design requires complex fabrication methods, and is therefore difficult to scale.
The fluxonium architecture has achieved among the strongest coherence for any solid-state superconducting qubit, with millisecond-level coherence times. Fluxoniums are a candidate for a qubit in a quantum processor, with some companies like D-Wave, Atlantic Quantum, and Qilimanjaro focused specifically on developing fluxonium-based quantum computing hardware.
Background
The first successful superconducting qubits were charge qubits, also known as Cooper boxes.
“Fluxonium” enters the record as superconducting qubit architecture. Crown Archives preserves that source wording while asking what Fluxonium, superconducting and qubit can confirm, complicate or overturn.
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This entry incorporates text from “Fluxonium” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.