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arXiv · 2412.18458

Hardware-aware Circuit Cutting and Distributed Qubit Mapping for Connected Quantum Systems

Abstract

Quantum computing offers unparalleled computational capabilities but faces significant challenges, including limited qubit counts, diverse hardware topologies, and dynamic noise/error rates, which hinder scalability and reliability. Distributed quantum computing, particularly chip-to-chip connections, has emerged as a solution by interconnecting multiple processors to collaboratively execute large circuits. While hardware advancements, such as IBM's Quantum Flamingo, focus on improving inter-chip fidelity, limited research addresses efficient circuit cutting and qubit mapping in distributed systems. This project introduces DisMap, a self-adaptive, hardware-aware framework for chip-to-chip distributed quantum systems. DisMap analyzes qubit noise and error rates to construct a virtual system topology, guiding circuit partitioning, and distributed qubit mapping to minimize SWAP overhead and enhance fidelity. Implemented with IBM Qiskit and compared with the state-of-the-art, DisMap achieves up to a 20.8\% improvement in fidelity and reduces SWAP overhead by as much as 80.2\%, demonstrating scalability and effectiveness in extensive evaluations on real quantum hardware topologies.

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Zefan Du, Yanni Li, Zijian Mo, Wenqi Wei, Juntao Chen, Rajkumar Buyya, Ying Mao. 2024-12-24. Hardware-aware Circuit Cutting and Distributed Qubit Mapping for Connected Quantum Systems. https://arxiv.org/abs/2412.18458

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