Quantum computers (QCs) aim to disrupt the status-quo of computing -- replacing traditional systems and platforms that are driven by digital circuits and modular software -- with hardware and software that operates on the principle of quantum mechanics. QCs that rely on quantum mechanics can exploit quantum circuits (i.e., quantum bits for manipulating quantum gates) to achieve "quantum computational supremacy" over traditional, i.e., digital computing systems. Currently, the issues that impede mass-scale adoption of quantum systems are rooted in the fact that building, maintaining, and/or programming QCs is a complex and radically distinct engineering paradigm when compared to challenges of classical computing and software engineering. Quantum service orientation is seen as a solution that synergises the research on service computing and quantum software engineering (QSE) to allow developers and users to build and utilise quantum software services based on pay-per-shot utility computing model. The pay-per-shot model represents a single execution of instruction on quantum processing unit and it allows vendors (e.g., Amazon Braket) to offer their QC platforms, simulators, software services etc. to enterprises and individuals who do not need to own or maintain quantum systems. This research contributes by 1) developing a reference architecture for enabling quantum computing as a service, 2) implementing microservices with the quantum-classic split pattern as an architectural use-case, and 3) evaluating the reference architecture based on feedback by 22 practitioners. In the QSE context, the research focuses on unifying architectural methods and service-orientation patterns to promote reuse knowledge and best practices to tackle emerging and futuristic challenges of architecting and implementing Quantum Computing as a Service (QCaaS).

翻译：量子计算机旨在颠覆计算领域的现状——用基于量子力学原理的硬件和软件取代由数字电路和模块化软件驱动的传统系统与平台。依赖量子力学的量子计算机可利用量子电路（即用于操控量子门的量子比特）实现相对于传统数字计算系统的"量子计算优越性"。当前阻碍量子系统大规模采用的问题根植于以下事实：相较于经典计算与软件工程的挑战，构建、维护和/或编程量子计算机是一种复杂且根本不同的工程范式。量子服务导向被视为一种解决方案，它协同服务计算研究与量子软件工程（QSE）的成果，使开发者和用户能够基于按次付费的效用计算模型构建和利用量子软件服务。按次付费模型代表在量子处理单元上执行单条指令，允许供应商（如Amazon Braket）向无需拥有或维护量子系统的企业和个人提供其量子计算平台、模拟器、软件服务等。本研究贡献如下：1）开发一种实现量子计算即服务的参考架构；2）以量子-经典分离模式实现微服务作为架构用例；3）基于22位从业者的反馈对参考架构进行评价。在QSE背景下，本研究聚焦于统一架构方法与服务导向模式，以促进知识复用和最佳实践，应对量子计算即服务（QCaaS）架构设计与实现中新兴及未来的挑战。