Engineers Link Fluxonium Gate Speed to Qubit-Pad Geometry

Engineers have numerically demonstrated ultrafast, high-fidelity two-qubit gates in two-dimensional fluxonium architectures by carefully engineering the geometry of qubit pads, a result challenging the previously held belief that capacitive loading posed a fundamental barrier to scaling these quantum processors. Fluxonium qubits offer millisecond-scale coherence times, positioning them as a strong candidate for building practical, scalable quantum computers. Researchers at the Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area, Shenzhen, China identified parasitic capacitances within Josephson junctions and arrays as the dominant source of capacitive loading hindering the move to 2D designs. Their work reveals…