IEEE Transactions on Quantum Engineering

Optimized Quantum Circuit Partitioning Across Multiple Quantum Processors

Eneet Kaur, Shahrooz Pouryousef, Hassan Shapourian, Jiapeng Zhao, Michael Kilzer, Ramana Rao Kompella, Reza Nejabati

Published Jan 1, 2025• 6 citations

Abstract

This paper addresses the challenge of scaling quantum computing by employing distributed quantum algorithms across multiple processors. As quantum circuits grow in complexity, efficiently managing the entanglement resources required for communication between quantum processing units (QPUs) becomes increasingly critical. We propose novel methods to optimize entanglement consumption while accounting for network constraints. Our approach leverages graph partitioning techniques to optimize both qubit teleportation and gate teleportation, minimizing the number of Einstein-Podolsky-Rosen (EPR) pairs required to execute general quantum circuits. Additionally, we formulate an integer linear program (ILP) to further reduce entanglement requirements by mapping the logical resources of partitioned circuits to the physical constraints of the underlying quantum network. Finally, we analyze the entanglement cost for implementing the Quantum Fourier Transform (QFT) across multiple QPUs, employing an approach that exploits the circuit's structure to minimize total entanglement consumption. These contributions provide a pathway to scalable and resource-efficient distributed quantum computing.

DOI: 10.1109/tqe.2025.3623158

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