As quantum computing enters the Utility Era, realizing near-term advantage relies heavily on Hybrid Variational Quantum Algorithms (VQAs). These algorithms require a tightly coupled, iterative loop between a classical CPU optimizer and a Quantum Processing Unit (QPU). However, current quantum cloud access models are bottlenecked by decoupled batch-queues that sever this loop, introducing massive Time-to-Next-Shot (TTNS) latency. This delay inflates convergence time from minutes to hours and exposes the computation to quantum hardware drift, degrading algorithmic fidelity. Unlike prior work that relies on resource-wasting static hardware reservations or state-oblivious, stateless functions, we propose EFaaS, a novel serverless middleware designed specifically for hybrid quantum workflows. EFaaS fundamentally departs from existing architectures by treating classical parameter optimization and quantum circuit execution as entangled, session-aware events. Our main technical innovations are threefold: (1) a Calibration-Aware placement strategy that dynamically routes circuits to QPUs with warm calibration caches, circumventing cold-start penalties, (2) a Dual-Resource Fair Queuing scheduler that maximizes quantum utilization by strictly prioritizing active iterative loops, and (3) the "EF-QuantumFuture" programming abstraction, a novel primitive enabling classical speculative execution to mask compute latency. Across the evaluated baselines, EFaaS achieves TTNS reductions of 11.4%-94.3%, QDC gains of 2.02%-15.78% points, and convergence speedups of 83.2%-98.3%, while eliminating drift penalties.
As quantum computing enters the Utility Era, realizing near-term advantage relies heavily on Hybrid Variational Quantum Algorithms (VQAs). These algorithms require a tightly coupled, iterative loop between a classical CPU optimizer and a Quantum Processing Unit (QPU). However, current quantum cloud access models are bottlenecked by decoupled batch-queues that sever this loop, introducing massive Time-to-Next-Shot (TTNS) latency. This delay inflates convergence time from minutes to hours and exposes the computation to quantum hardware drift, degrading algorithmic fidelity. Unlike prior work that relies on resource-wasting static hardware reservations or state-oblivious, stateless functions, we propose EFaaS, a novel serverless middleware designed specifically for hybrid quantum workflows. EFaaS fundamentally departs from existing architectures by treating classical parameter optimization and quantum circuit execution as entangled, session-aware events. Our main technical innovations are threefold: (1) a Calibration-Aware placement strategy that dynamically routes circuits to QPUs with warm calibration caches, circumventing cold-start penalties, (2) a Dual-Resource Fair Queuing scheduler that maximizes quantum utilization by strictly prioritizing active iterative loops, and (3) the "EF-QuantumFuture" programming abstraction, a novel primitive enabling classical speculative execution to mask compute latency. Across the evaluated baselines, EFaaS achieves TTNS reductions of 11.4%-94.3%, QDC gains of 2.02%-15.78% points, and convergence speedups of 83.2%-98.3%, while eliminating drift penalties.
Introduction Hybrid Variational Quantum Algorithms (VQAs) present a highly viable pathway to near-term quantum utility; however, their performance is fundamentally bottlenecked by classical-quantum communication latency in Quantumas-a-Service (QaaS) environments. Methods This paper proposes an optimized classical-quantum orchestration architecture designed to minimize cloud-induced latency and maximize Quantum Processing Unit (QPU) active compute time. By implementing edge-colocated classical optimizers alongside batched parameter-shift gradient evaluations, the system circumvents stateless cloud API barriers. Results Benchmarking across parameterized quantum circuits ranging from 15 to 50 qubits demonstrates an 84% reduction in network-induced QPU idle time. The framework yields a 3.2 × speedup in overall convergence time for the Quantum Approximate Optimization Algorithm (QAOA) and up to a 98% reduction in classical API call overhead compared to standard RESTful QaaS execution models. Discussion These quantitative findings demonstrate that tightly coupled hybrid co-processing, physically adjacent to the control electronics, is critical for extending the computational bound of Noisy Intermediate-Scale Quantum (NISQ) devices.
Abstract The integration of cloud computing architectures with quantum computational models represents a significant paradigm shift in the field of large-scale data analysis. While quantum processors possess the theoretical capability to solve complex statistical and logistical problems exponentially faster than classical systems, deploying them within conventional cloud environments introduces severe performance bottlenecks. These challenges primarily revolve around network latency, quantum state decoherence, and the inadequacies of classical resource provisioning algorithms. In this paper, we explore the performance issues associated with hybrid quantum-cloud infrastructures and propose a structured decision-making and scheduling framework. By analyzing deployment constraints, cryptographic overheads, and hardware limitations, this study highlights the critical pathways and ethical considerations necessary for standardizing Quantum-as-a-Service (QaaS) in modern enterprise datacenters. Keywords: Quantum processors, Quantum-as-a-Service(QaaS), makespan 1.Introduction The integration of cloud computing and quantum computation represents a crucial frontier for the future of complex data analysis. Cloud computing has revolutionized the modern information technology landscape by transitioning computational resources from localized, purchased products to highly scalable, on-demand services delivered over the internet. Simultaneously, quantum computing offers unprecedented computational advantages through fundamental physical phenomena like entanglement and superposition, enabling the resolution of highly complex logistical, chemical, and statistical problems. However, merging these two distinct technological domains into a unified framework introduces severe performance bottlenecks related to dynamic resource provisioning, network communication latency, and task scheduling. The primary problem lies in the efficient execution of large-scale data analysis pipelines that make both classical datacenters and quantum processing units (QPUs). Existing approaches are demonstrably insufficient for managing this hybrid computing environment for two main reasons. First, conventional cloud load balancing and resource allocation algorithms are designed solely for deterministic classical virtual machines, fundamentally failing to account for the unique coherence times, error rates, and state preparation constraints of quantum hardware. Fig 1.1 shows Cloud balancing. Second,current cryptographic protocols designed for delegated quantum computing , while excellent at ensuring the blindness and security of user data, impose substantial communication and entangling overheads that severely degrade end-to-end performance in real-world datacenter along with Circuit diagram in Fig.1.2. Figure 1.1 Cloud Balancing with web servers To address these critical performance issues, this paper introduces a novel architectural approach designed specifically for hybrid quantum-cloud systems. We aim to bridge the gap between theoretical quantum potential and practical cloud deployment. Specifically, our work makes the following contributions: We propose a structured, hybrid decision-making and scheduling framework that dynamically partitions and routes data analysis tasks between classical cloud servers and quantum nodes. We formulate a comprehensive, hypothetical evaluation methodology to simulate the makespan and resource utilization of this hybrid system, identifying key latency bottlenecks in delegated quantum operations. Fig 1.2. Quantum Circuit diagram 2.Classical Cloud Computing The first category of related work focuses on resource management and provisioning in classical cloud computing. Traditional methods in this domain emphasize minimizing the computational makespan of tasks through selective heuristics, such as min-min and max-min scheduling algorithms, which allocate virtual machines based on fluctuating task demands. Furthermore, comprehensive load balancing schemes have been developed to ensure efficient resource utilization in accordance with strict Service Level Agreements (SLAs), allowing resources to be provisioned on a pay-as-you-go basis. While these classical models demonstrate robust strengths in minimizing computational wait times and maximizing server efficiency, their fundamental weakness is their inability to schedule probabilistic and highly sensitive quantum operations. In contrast to these purely classical frameworks, our proposed work directly integrates quantum-specific hardware constraints, such as state preparation delays and decoherence windows, into the provisioning logic. The second category addresses broader enterprise cloud adoption and organizational decision-making frameworks. Research in this area highlights the necessity for generic, multi-criteria decision frameworks that evaluate cloud infrastructures beyond mere cost considerations, factoring in specific enterprise risks, benefits, and IT support metrics. Additionally, numerous studies have developed strategic roadmaps for Small and Medium Enterprises (SMEs) to navigate complex interoperability, knowledge, and security challenges during cloud migration. Although these frameworks provide excellent strategic guidance for adopting standard classical services, they lack operational mechanisms for managing the performance issues introduced by bleeding-edge quantum co-processors. Our work builds upon these established enterprise decision-making structures by providing a functional, low-level deployment pipeline tailored for hybrid operations. The third category explores the theoretical foundations of delegated quantum computing and interdisciplinary quantum applications. Delegated quantum computing allows clients with extremely low computational capabilities to securely outsource demanding tasks to a powerful quantum server, often utilizing measurement-based models and complex prepare-and-send communication paradigms to preserve data blindness. Concurrently, quantum computing frameworks have been utilized to explore deep interdisciplinary problems—ranging from physics paradoxes to advanced chemical modeling—demonstrating vast analytical potential. The primary weakness of this category is that much of the academic research remains focused on abstract theoretical protocols or isolated quantum circuits, rather than addressing the physical infrastructure pitfalls and massive scale required for cloud integration. This paper bridges that gap by embedding delegated quantum paradigms within a concrete, performance-oriented enterprise cloud architecture. 3.Hybrid Quantum-Cloud To tackle the performance issues inherent in hybrid data analysis, we propose a modular Hybrid Quantum-Cloud Provisioning Framework. The system follows a structured, numbered pipeline designed to seamlessly route computational tasks across heterogeneous hardware. First, classical user requests are ingested by a central cloud load balancer that analyzes the computational complexity and algorithmic requirements of the incoming dataset. Second, the system employs a multi-criteria decision engine to partition the workflow; classical data preprocessing is routed to standard virtual machines, while complex optimization components are packaged as isolated quantum circuits. Third, the framework utilizes a delegated quantum computing protocol to securely transmit the quantum state from the classical node to the QPU, applying a prepare-and-send methodology to preserve data blindness during execution. Finally, the resulting quantum measurements are returned to the classical cloud for post-processing and aggregation before the final analysis is delivered to the end user. The core design choice in this approach is the adaptation of selective scheduling heuristics to manage the delicate interaction between classical datacenters and quantum nodes. Traditional task allocation algorithms are augmented to treat QPUs as highly specialized, time-shared resources with exceptionally strict execution windows dictated by qubit decoherence times. Furthermore, we utilize an ad hoc resource harvesting concept for the classical preprocessing stages, allowing sporadic, non-exclusive classical resources to rapidly feed structured data into the highly controlled quantum environment. This strict division of labor ensures that the expensive, high-maintenance quantum hardware is never left idle waiting for classical data transformations, thereby optimizing the overall makespan and mitigating critical performance bottlenecks. To validate the efficacy of this proposed framework, we outline a comprehensive hypothetical evaluation plan. We propose extending a standard cloud simulation environment, such as CloudSim, by integrating a custom quantum execution module that mathematically models qubit gate latencies, state preparation times, and network communication overheads. The hypothetical evaluation will benchmark our hybrid scheduling algorithm against strict First-Come-First-Serve (FCFS) provisioning policies across varying data analysis workload intensities. By tracking the total task makespan and server utilization rates, we anticipate demonstrating that intelligent algorithmic partitioning significantly reduces the performance degradation typically associated with delegated quantum computing overheads. 4.Practical implications The deployment of hybrid quantum-cloud systems carries significant practical implications for the future of enterprise IT infrastructure. From a deployment perspective, organizations will no longer need to invest heavily in fragile, independent quantum hardware; instead, they will consume computation through standardized cloud providers. This shift mandates a reevaluation of existing academic cloud research, pushing industry professionals to move beyond small-scale toy deployments and embrace complex, data-center-level abstractions that in
High-performance computing (HPC) has evolved over decades through multiple architectural transitions, from vector supercomputers to massively parallel CPU clusters and GPU-accelerated systems, continuously expanding the frontier of scientific discovery. With the emergence of quantum processing units (QPUs) as practical computational accelerators, a new opportunity arises to further extend this trajectory by integrating quantum and classical computing paradigms. Building on the emerging vision of Quantum Integrated High-Performance Computing (QHPC), this paper contributes a full-stack layered architecture that integrates QPUs as first-class accelerators within, not merely alongside, the classical HPC software and hardware stack, with tight, on-premise quantum-classical coupling as its defining characteristic. The architecture comprises of unified resource management, quantum-aware scheduling, hybrid workflow orchestration, middleware and programming abstraction, interconnect technologies, and a tiered execution model enabling seamless workload partitioning across classical and quantum backends. A central aspect of this architecture is a strong user requests abstraction layer that exposes heterogeneous resources through a unified job submission interface, similar in spirit to existing schedulers such as Slurm, allowing users to describe workloads in a consistent template independent of underlying compute type or location. Drawing insights from prior accelerator integration eras, we outline how QHPC can support emerging workloads in quantum chemistry, materials discovery, combinatorial optimization, and climate modeling. We conclude by highlighting open challenges in building scalable, reliable, and programmable quantum-classical infrastructures that seamlessly connect global users to heterogeneous compute resources for future quantum-classical HPC ecosystems.
Quantum computing is increasingly accessed through cloud-based hybrid environments, but practical adoption depends on more than exposing remote quantum backends. It also requires managed abstractions for orchestrating classical and quantum stages, handling queues, binding backends, and integrating surrounding workflow logic. This paper presents a comprehensive survey of Quantum Serverless from that perspective. Our contribution is twofold: (1) we consolidate the key architectural components of Quantum Serverless into a unified reference architecture; and (2) we evaluate current industry and research offerings through a KPI-driven framework covering ecosystem coverage, service operability, queue handling, pricing flexibility, near-real-time readiness, and production maturity. Using this framework, we analyze 18 quantum cloud platforms and show that the ecosystem is growing but remains unevenly mature. Queue-based execution is already a baseline capability, whereas stronger serverless characteristics, such as Function-as-a-Service, Containers-as-a-Service, near-real-time responsiveness, and production readiness, remain limited. Overall, current Quantum Serverless is best understood as a queue-driven hybrid orchestration model rather than a fully mature cloud-native serverless layer. The survey identifies the main maturity gaps and outlines directions for future development.
High-performance computing (HPC) has evolved over decades through multiple architectural transitions, from vector supercomputers to massively parallel CPU clusters and GPU-accelerated systems, continuously expanding the frontier of scientific discovery. With the emergence of quantum processing units (QPUs) as practical computational accelerators, a new opportunity arises to further extend this trajectory by integrating quantum and classical computing paradigms. Building on the emerging vision of Quantum Integrated High-Performance Computing (QHPC), this paper contributes a full-stack layered architecture that integrates QPUs as first-class accelerators within, not merely alongside, the classical HPC software and hardware stack, with tight, on-premise quantum–classical coupling as its defining characteristic. The architecture comprises of unified resource management, quantum-aware scheduling, hybrid workflow orchestration, middleware and programming abstraction, interconnect technologies, and a tiered execution model enabling seamless workload partitioning across classical and quantum backends. A central aspect of this architecture is a strong user requests abstraction layer that exposes heterogeneous resources through a unified job submission interface, similar in spirit to existing schedulers such as Slurm, allowing users to describe workloads in a consistent template independent of underlying compute type or location. Drawing insights from prior accelerator integration eras, we outline how QHPC can support emerging workloads in quantum chemistry, materials discovery, combinatorial optimization, and climate modeling. We conclude by highlighting open challenges in building scalable, reliable, and programmable quantum–classical infrastructures that seamlessly connect global users to heterogeneous compute resources for future quantum–classical HPC ecosystems.
We present Qurator, a quantum-classical task scheduler that jointly optimizes queue time and circuit fidelity across heterogeneous architectures. Qurator models hybrid workloads as dynamic DAGs with explicit quantum semantics, including entanglement dependencies, synchronization barriers, no-cloning constraints, and circuit cutting and merging decisions. Fidelity is estimated through a unified logarithmic success score that reconciles incompatible calibration data from IBM, IonQ, IQM, Rigetti, AQT, Pasqal and other providers into a canonical set of gate error, readout fidelity, and decoherence terms. We evaluate Qurator on a simulator driven by four months of real queue data using circuits from the Munich Quantum Toolkit benchmark suite. Across load conditions from 5 to 35,000 quantum tasks with up to 120,000 classical tasks, Qurator stays within 1% of the highest-fidelity baseline at low load, achieves 30-75% queue time reduction at high load, all at a fidelity cost bounded by a user-specified target while improving on list and fair schedulers as well as state of the art schedulers on both metrics.