An End-to-End Distributed Quantum Circuit Simulator

2025-11-24

AI Summary

Existing distributed quantum computing (DQC) research lacks a circuit-level simulator supporting heterogeneous backends, noisy communication links, and distributed execution—hindering architectural evaluation and optimization. This paper introduces SimDisQ, the first end-to-end circuit-level simulator for distributed quantum computing. It integrates realistic noise models for superconducting and trapped-ion quantum processing units (QPUs), fidelity-aware entanglement distribution modeling, and communication channel noise. SimDisQ enables multi-QPU co-simulation under realistic constraints. Its key contributions are: (1) the first quantitative analysis of architectural trade-offs, communication fidelity limitations, and distributed circuit optimization in DQC; and (2) a scalable, automated simulation toolkit seamlessly interoperable with mainstream quantum software ecosystems. Benchmarking demonstrates that, under typical entanglement distribution fidelities, heterogeneous distributed execution significantly improves overall circuit fidelity—validating the practical viability of DQC.

Technology Category

• Search and Optimization: Distributed Search
• Machine Learning: Quantum Machine Learning
• Constraint Satisfaction and Optimization: Distributed CSP/Optimization

Application Category

• Security and Privacy: Blockchains and distributed ledgers
• Systems and Infrastructure for Web, Mobile and WoT: Federated Web and WoT systems, including distributed, federated and edge-based data processing
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems

Abstract

Quantum computing has made substantial progress in recent years; however, its scalability remains constrained on a monolithic quantum processing unit (QPU). Distributed quantum computing (DQC) offers a pathway by coordinating multiple QPUs to execute large-scale circuits. Yet, DQC still faces practical barriers, as its realization depends on advances in hardware-level components such as quantum transducers and high-fidelity entanglement-distribution modules. While these technologies continue to improve, mature DQC platforms remain unavailable. In the meantime, researchers need to assess the benefits of DQC and evaluate emerging DQC designs, but the software ecosystem lacks a circuit-level simulator that models heterogeneous backends, noisy connections, and distributed execution. To fill this gap, this paper proposes SimDisQ, the first end-to-end circuit-level DQC simulator, composed of a set of novel DQC-oriented automated simulation toolkits and communication noise models that can interoperate with existing toolkits in mainstream quantum software ecosystems. Leveraging circuit-level simulation capabilities, SimDisQ enables quantitative exploration of architectural design trade-offs, communication fidelity constraints, and new circuit optimization challenges introduced by DQC, providing a foundation for future research in this promising direction. Benchmarking experiments using SimDisQ respond to a couple of open questions in the community; for example, noisy simulation of superconducting and trapped-ion qubits, with a reasonable entanglement- distribution fidelity, reveal that heterogeneous QPUs can indeed yield higher execution fidelity.

Problem

• Simulating distributed quantum circuits with heterogeneous backends
• Modeling noisy connections and distributed execution challenges
• Evaluating architectural trade-offs and communication fidelity constraints

Innovation

• SimDisQ enables end-to-end distributed quantum circuit simulation
• It models heterogeneous backends with noisy communication links
• Provides automated toolkits for architectural design exploration