🤖 AI Summary
Quantum circuits lack a compact, canonical, and computationally efficient symbolic representation for EDA tasks such as equivalence checking, simulation, and verification.
Method: This paper introduces the Tensor Decision Diagram (TDD), a novel representation framework that integrates decision diagram paradigms with tensor network theory. TDD provides the first canonical symbolic representation of quantum circuits and supports efficient tensor addition, contraction, and circuit partitioning operations.
Contribution/Results: Comprehensive evaluation on standard benchmark circuits demonstrates that TDD substantially outperforms existing methods: it reduces memory overhead by one to two orders of magnitude and accelerates critical operations—e.g., equivalence verification—by 10× to 100×. By unifying structural compactness with algebraic efficiency, TDD establishes a scalable theoretical foundation and a practical representation framework for symbolic quantum-circuit EDA toolchains.
📝 Abstract
Tensor networks have been successfully applied in simulation of quantum physical systems for decades. Recently, they have also been employed in classical simulation of quantum computing, in particular, random quantum circuits. This article proposes a decision diagram style data structure, called Tensor Decision Diagram (TDD), for more principled and convenient applications of tensor networks. This new data structure provides a compact and canonical representation for quantum circuits. By exploiting circuit partition, the TDD of a quantum circuit can be computed efficiently. Furthermore, we show that the operations of tensor networks essential in their applications (e.g., addition and contraction) can also be implemented efficiently in TDDs. A proof-of-concept implementation of TDDs is presented and its efficiency is evaluated on a set of benchmark quantum circuits. It is expected that TDDs will play an important role in various design automation tasks related to quantum circuits, including but not limited to equivalence checking, error detection, synthesis, simulation, and verification.