Enhancing Fault-Tolerant Surface Code Decoding with Iterative Lattice Reweighting

Understand

Efficient and realistic error decoding is crucial for fault-tolerant quantum computation (FTQC) on near-term devices.

• While decoding is a classical post-processing task, its effectiveness depends on accurately modeling quantum noise, which is hardware-dependent.
• In particular, correlated bit-flip ($X$) and phase-flip ($Z$) errors often arise under circuit-level noise.
• We introduce the Iterative Reweighting Minimum-Weight Perfect Matching (IRMWPM) decoder, which systematically incorporates such correlations to enhance quantum error correction.