Experimental realization of ultra-high fidelity qubit operations with tunable fluxonium qubits

High-fidelity gates are critical for reducing the number of physical qubits required by quantum error correction. A main challenge for realizing high-fidelity gates is balancing controllability with coherence times. Fluxonium has reduced sensitivity to multiple noise sources, thereby exhibiting high coherence while maintaining large anharmonicity and strong coupling between circuits. These properties make fluxonium a promising qubit design for the next generation of superconducting quantum processors. However, due to its lower transition frequency, a fluxonium always stabilizes at a thermal state. Therefore, an active qubit reset needs to be implemented, in addition to a universal gate set. In this talk, we will demonstrate an efficient qubit reset and ultra-high fidelity single and two-qubit gates in a system with two coupled fluxonium qubits. The technologies demonstrated here are compatible with current methods for scaling up a multi-qubit system.