By giving qubits a 'third state,' we've enabled hardware that can detect and report its own errors.
Using transmon qutrits as 'erasure qubits' allows the system to flag its own failures, extending the effective qubit lifetime by 10x. It shifts error correction from software overhead to a built-in hardware feature.
Hardware-Efficient Erasure Qubits With Superconducting Transmon Qutrits
arXiv · 2604.08672
Quantum error correction using erasure qubits offers higher fault-tolerant thresholds and improved scaling by converting dominant physical errors into detectable erasures. In superconducting circuits, erasure qubits can be constructed using the dual-rail approach, which, however, requires additional qubit-count overhead and tailored coupling elements. Here, we demonstrate a hardware-efficient scheme that operates transmon qutrits as erasure qubits, which is compatible with standard superconducti