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arXiv · 2403.17205

Revisiting the Mapping of Quantum Circuits: Entering the Multi-Core Era

Pau Escofet·Anabel Ovide·Medina Bandic·Luise Prielinger·Hans van Someren·Sebastian Feld·Eduard Alarcón·Sergi Abadal·Carmen G. Almudéver
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Abstract

Quantum computing represents a paradigm shift in computation, offering the potential to solve complex problems intractable for classical computers. Although current quantum processors already consist of a few hundred of qubits, their scalability remains a significant challenge. Modular quantum computing architectures have emerged as a promising approach to scale up quantum computing systems. This paper delves into the critical aspects of distributed multi-core quantum computing, focusing on quantum circuit mapping, a fundamental task to successfully execute quantum algorithms across cores while minimizing inter-core communications. We derive the theoretical bounds on the number of non-local communications needed for random quantum circuits and introduce the Hungarian Qubit Assignment (HQA) algorithm, a multi-core mapping algorithm designed to optimize qubit assignments to cores with the aim of reducing inter-core communications. Our exhaustive evaluation of HQA against state-of-the-art circuit mapping algorithms for modular architectures reveals a $4.9\times$ and $1.6\times$ improvement in terms of execution time and non-local communications, respectively, compared to the best performing algorithm. HQA emerges as a very promising scalable approach for mapping quantum circuits into multi-core architectures, positioning it as a valuable tool for harnessing the potential of quantum computing at scale.

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Pau Escofet, Anabel Ovide, Medina Bandic, Luise Prielinger, Hans van Someren, Sebastian Feld, Eduard Alarcón, Sergi Abadal, Carmen G. Almudéver. 2024-03-25. Revisiting the Mapping of Quantum Circuits: Entering the Multi-Core Era. https://doi.org/10.1145/3655029

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