Scalable quantum computing architectures increasingly rely on multi-core designs, where qubits are distributed across multiple processing cores interconnected through a quantum Network-on-Chip (NoC). In such systems, inter-core communication is typically realized through entanglement-assisted quantum teleportation, making efficient entanglement generation critical for performance. In this paper, we perform a comparative study of three entanglement management paradigms for multi-core quantum processors: reactive on-demand generation (ODG), proactive continuous pre-generation (CGP), and an adaptive continuous pre-generation approach (ACGP). While ODG generates entanglement only when required, CGP reduces average teleportation latency by pre-generating EPR pairs in the background. To improve upon this, we propose ACGP which dynamically adjusts entanglement generation probabilities based on observed inter-core communication patterns. We evaluate these approaches using an extended SeQUeNCe simulator on mesh-based multi-core architectures on real benchmark circuits. Results show that ACGP significantly reduces average teleportation latency compared to ODG and CGP. Although pre-generation introduces fidelity degradation due to storage time, entanglement purification effectively restores fidelity with minimal impact on latency. These results demonstrate that adaptive entanglement managements can substantially improve communication efficiency in scalable quantum multi-core systems.
Scalable quantum computing architectures increasingly rely on multi-core designs, where qubits are distributed across multiple processing cores interconnected through a quantum Network-on-Chip (NoC). In such systems, inter-core communication is typically realized through entanglement-assisted quantum teleportation, making efficient entanglement generation critical for performance. In this paper, we perform a comparative study of three entanglement management paradigms for multi-core quantum processors: reactive on-demand generation (ODG), proactive continuous pre-generation (CGP), and an adaptive continuous pre-generation approach (ACGP). While ODG generates entanglement only when required, CGP reduces average teleportation latency by pre-generating EPR pairs in the background. To improve upon this, we propose ACGP which dynamically adjusts entanglement generation probabilities based on observed inter-core communication patterns. We evaluate these approaches using an extended SeQUeNCe simulator on mesh-based multi-core architectures on real benchmark circuits. Results show that ACGP significantly reduces average teleportation latency compared to ODG and CGP. Although pre-generation introduces fidelity degradation due to storage time, entanglement purification effectively restores fidelity with minimal impact on latency. These results demonstrate that adaptive entanglement managements can substantially improve communication efficiency in scalable quantum multi-core systems.
Multi-core quantum computing architectures offer a promising and scalable solution to the challenges of integrating large number of qubits into existing monolithic chip design. However, the issue of transferring quantum information across the cores remains unresolved. Quantum Teleportation offers a potential approach for efficient qubit transfer, but existing methods primarily rely on centralized interconnection mechanisms for teleportation, which may limit scalability and parallel communication. We proposes a decentralized framework for teleportation in multi-core quantum computing systems, aiming to address these limitations. We introduce two variants of teleportation within the decentralized framework and evaluate their impact on reducing end-to-end communication delay and quantum circuit depth. Our findings demonstrate that the optimized teleportation strategy, termed two-way teleportation, results in a substantial 40% reduction in end-to-end communication latency for synthetic benchmarks and a 30% reduction for real benchmark applications, and 24% decrease in circuit depth compared to the baseline teleportation strategy. These results highlight the significant potential of decentralized teleportation to improve the performance of large-scale quantum systems, offering a scalable and efficient solution for future quantum architectures.
Multi-core quantum computing architectures offer a promising and scalable solution to the challenges of integrating large number of qubits into existing monolithic chip design. However, the issue of transferring quantum information across the cores remains unresolved. Quantum Teleportation offers a potential approach for efficient qubit transfer, but existing methods primarily rely on centralized interconnection mechanisms for teleportation, which may limit scalability and parallel communication. We proposes a decentralized framework for teleportation in multi-core quantum computing systems, aiming to address these limitations. We introduce two variants of teleportation within the decentralized framework and evaluate their impact on reducing end-to-end communication delay and quantum circuit depth. Our findings demonstrate that the optimized teleportation strategy, termed two-way teleportation, results in a substantial 40% reduction in end-to-end communication latency for synthetic benchmarks and a 30% reduction for real benchmark applications, and 24% decrease in circuit depth compared to the baseline teleportation strategy. These results highlight the significant potential of decentralized teleportation to improve the performance of large-scale quantum systems, offering a scalable and efficient solution for future quantum architectures.
The scalability of quantum computing is constrained by the physical and architectural limitations of monolithic quantum processors. Modular multi-core quantum architectures, which interconnect multiple quantum cores (QCs) via classical and quantum-coherent links, offer a promising alternative to address these challenges. However, transitioning to a modular architecture introduces communication overhead, where classical communication plays a crucial role in executing quantum algorithms by transmitting measurement outcomes and synchronizing operations across QCs. Understanding the impact of classical communication on execution time is therefore essential for optimizing system performance. In this work, we introduce qcomm , an open-source simulator designed to evaluate the role of classical communication in modular quantum computing architectures. qcomm provides a high-level execution and timing model that captures the interplay between quantum gate execution, entanglement distribution, teleportation protocols, and classical communication latency. We conduct an extensive experimental analysis to quantify the impact of classical communication bandwidth, interconnect types, and quantum circuit mapping strategies on overall execution time. Furthermore, we assess classical communication overhead when executing real quantum benchmarks mapped onto a cryogenically-controlled multi-core quantum system. Our results show that, while classical communication is generally not the dominant contributor to execution time, its impact becomes increasingly relevant in optimized scenarios—such as improved quantum technology, large-scale interconnects, or communication-aware circuit mappings. These findings provide useful insights for the design of scalable modular quantum architectures and highlight the importance of evaluating classical communication as a performance-limiting factor in future systems.
In the quest of large-scale quantum computers, multi-core distributed architectures are considered a compelling alternative to be explored. A crucial aspect in such approach is the stringent demand on communication among cores when qubits need to interact, which conditions the scalability potential of these architectures. In this work, we address the question of how the cost of the communication among cores impacts on the viability of the quantum multi-core approach. Methodologically, we consider a design space in which architectural variables (number of cores, number of qubits per core), application variables for several quantum benchmarks (number of qubits, number of gates, percentage of two-qubit gates) and inter-core communication latency are swept along with the definition of a figure of merit. This approach yields both a qualitative understanding of trends in the design space and companion dimensioning guidelines for the architecture, including optimal points, as well as quantitative answers to the question of beyond which communication performance levels the multi-core architecture pays off. Our results allow to determine the thresholds for inter-core communication latency in order for multi-core architectures to outperform single-core quantum processors.
Scaling quantum computing beyond a single device requires networking many quantum processing units (QPUs) into a coherent quantum-HPC system. We propose the Modular Entanglement Hub (ModEn-Hub) architecture: a hub-and-spoke photonic interconnect paired with a real-time quantum network orchestrator. ModEn-Hub centralizes entanglement sources and shared quantum memory to deliver on-demand, high-fidelity Bell pairs across heterogeneous QPUs, while the control plane schedules teleportation-based non-local gates, launches parallel entanglement attempts, and maintains a small ebit cache. To quantify benefits, we implement a lightweight, reproducible Monte Carlo study under realistic loss and tight round budgets, comparing a naive sequential baseline to an orchestrated policy with logarithmically scaled parallelism and opportunistic caching. Across 1-128 QPUs and 2,500 trials per point, ModEn-Hub-style orchestration sustains about 90% teleportation success while the baseline degrades toward about 30%, at the cost of higher average entanglement attempts (about 10-12 versus about 3). These results provide clear, high-level evidence that adaptive resource orchestration in the ModEn-Hub enables scalable and efficient quantum-HPC operation on near-term hardware.
Scaling quantum computing beyond a single device requires networking many quantum processing units (QPUs) into a coherent distributed system. However, most quantum network proposals focus on physical link technologies or point-to-point entanglement generation, leaving the adaptive orchestration of entanglement as a shared resource largely unexplored. We introduce the Modular Entanglement Hub (ModEn-Hub), a hub-and-spoke photonic interconnect paired with a real-time orchestrator that centralizes entanglement generation, routing, and caching across heterogeneous QPUs. ModEn-Hub manages the full Bell-pair lifecycle—deciding which links to entangle, when to schedule teleportation-based non-local gates, and how to allocate a limited cache of stored ebits under loss and decoherence constraints. To illustrate the potential benefits, we perform a lightweight, reproducible Monte Carlo study based on simple but realistic models of photon loss, finite memory lifetime, and bounded time budgets, comparing a naïve sequential strategy to an orchestrated policy with limited parallel attempts and opportunistic reuse of cached entanglement. In our experiments across small-to-moderate network sizes, ModEn-Hub-style orchestration maintains substantially higher teleportation success probabilities than the baseline, albeit at the cost of more entanglement generation attempts. These results provide high-level evidence that adaptive, centrally coordinated resource management is a promising architectural pattern for scalable, near-term distributed quantum computing.