Erasure Qubits Based on an Integer Fluxonium

Within error correction architectures, erasure qubits can significantly improve error threshold and code distance by converting the most common errors in the system into detectable erasure errors. In superconducting circuits, erasure qubits have been implemented with dual-rail transmons and high-Q cavities. These designs have demonstrated improved logical state coherence and gate fidelity after erasure error correction. However, dual-rail architectures require more than a single physical qubit to implement one erasure qubit, thus increasing overhead. In this talk, we present an erasure qubit design based on a single integer fluxonium. We demonstrate basic characterization results of the integer fluxonium and assess its potential as an erasure qubit. The next phase of our work will involve implementing an erasure check protocol and quantifying the improvement in the logical state coherence time from erasure checks.