Equivalence Checking of Quantum Circuits via Path-Sum and Weighted Model Counting

Wei-Jia Huang

, 

Christophe Chareton

, 

Yu-Fang Chen

, 

Kai-Min Chung

, Min-Hsiu Hsieh, 

Alfons Laarman

, 

Jingyi Mei

出版日期

April 14, 2026

研究中心

量子計算研究所

發表資訊

TACAS 2026

主題

Quantum Computing

資源

PDF

內容目錄

Equivalence checking of quantum circuits is a central verification task in quantum computing, ensuring the correctness of circuit optimizations, hardware mappings, and compilation pipelines. Among the primary symbolic methods for this purpose, the path-sum formalism provides a compact representation with powerful reduction rules that yield a canonical form for the classically simulable Clifford fragment, but confluence fails beyond the Clifford fragment. We introduce a new weighted model counting (WMC) encoding for path-sums and combine it with the existing path-sum reductions to obtain a verifier that is both complete and efficient. Our method applies reductions whenever possible and invokes the WMC-based decision procedure on the residual path-sum, yielding a complete semantic check up to a global phase. We implement the approach and evaluate it on standard benchmarks. Results show that the hybrid method outperforms either component in isolation and competes with state-of-the-art tools.