EPJ Quantum Technology最新文献

Quantum computing has rapidly emerged as one of the fastest-growing research domains, driven by both technological breakthroughs and the promise of computational advantages over classical systems. This study presents a comprehensive bibliometric analysis of the global quantum computing literature from 1980 to 2025, comprising 31,662 publications indexed in Scopus and accumulating over 800,000 citations. Using advanced bibliometric techniques—including co-authorship mapping, keyword co-occurrence networks, co-citation analysis, and centrality measures—we characterize publication trends, institutional contributions, collaborative structures, and thematic evolution across the field. The results reveal exponential growth in output since 2015, led primarily by the United States, China, and Europe, with key institutions such as MIT, the Chinese Academy of Sciences, CNRS, and the University of Waterloo at the forefront. The intellectual structure exhibits a dual-core configuration, with foundational algorithmic work (e.g. Shor, Grover, Nielsen & Chuang) tightly connected to emerging NISQ-era applications such as quantum machine learning, cryptography, and hybrid algorithms. Keyword analysis reveals the progressive expansion from core quantum algorithms toward increasingly diverse applied domains in healthcare, finance, chemistry, energy, and climate modeling. Public funding bodies (e.g. NSFC, NSF, European Commission, DOE, DoD, MoST) and private-sector investment from major technology firms are jointly driving this translational acceleration. Together, these findings provide an integrated quantitative map of the field’s evolution, offering valuable insight for future scientific policy, international collaboration, and strategic funding initiatives.

We demonstrate the first violation of the Leggett-Garg inequality and time-order noninvariance on public quantum computers using genuine noninvasive measurements. By gathering sufficiently large statistics, we have been able to violate Leggett-Garg inequality and time-order invariance. The detailed analysis of the data on 10 qubit sets from 5 devices available on IBM Quantum and one on IonQ reveals violations beyond 5 standard deviations in almost all cases. We implemented our protocols using fractional gates, newly available on the IBM Heron devices, allowing us to benchmark them in application to weak measurements. The noninvasiveness is supported by a qualitative and quantitative agreement with the model of weak disturbance. Moreover, our data expose statistically significant deviations from theoretical predictions that exceed declared device error rates, establishing weak measurement protocols as a sensitive benchmark for quantum hardware. These advances transform public quantum computers into practical testbeds for probing foundational questions of realism and temporal order with unprecedented accessibility and precision.

The development and study of demonstration materials (DM) in quantum physics (QP) education has gained increasing attention in research, leading to a diverse range of approaches. In this scoping review, we examine 302 scientific publications on DM for QP education, categorising them by DM type and QP topics. We analyse the progression of research output from 2000 to 2023, highlighting different strategies in digital and haptic DM, as well as pedagogical considerations and gaps. We also performed an evaluation of the research field, assessing educational goals and challenges, methodological approaches, implementation strategies, and the reported effectiveness of DM.

Our analysis reveals a growing, yet uneven, distribution of DM across QP topics, an increased emphasis on quantum technology applications, and varying quality in studies on learning outcomes. While some DM are well established, others remain underexplored, particularly: DM that connect QP topics to a wide range of real world contexts, integrating multiple DM types and representations, and adapting materials for different audiences. We conclude by highlighting the critical need for “educational readiness” of DM. To advance QP education, future research must therefore focus on the effective integration of DM into practice, supported by comprehensive reporting on design principles, functionality, and implementation.

In distributed quantum computing, the final solution of a problem is usually achieved by catenating these partial solutions resulted from different computing nodes, but intolerable errors likely yield in this catenation process. In this paper, we propose a universal error correction scheme to reduce errors and obtain effective solutions. Then, we apply this error correction scheme to designing a distributed phase estimation algorithm that presents a basic tool for studying distributed Shor’s algorithm and distributed discrete logarithm algorithm as well as other distributed quantum algorithms. Our method may provide a universal strategy of error correction for a kind of distributed quantum computing.

Quantum technologies are rapidly emerging as a strategic priority for global political powers. Yet little is known about how policymakers across countries perceive the security implications of quantum technologies, even though such perceptions shape policy priorities and public understanding of technological threats. Drawing on securitization theory, we analyze parliamentary speeches from 2010 to 2024 across Australia, the United Kingdom, the United States, the European Union, and Singapore. Using computational social science tools, including a novel method based on large language models to quantify security emphasis, we report on three principal findings. First, attention and security framing vary markedly across legislatures, with the United States showing the highest intensity, the United Kingdom a moderate pattern, and Australia comparatively muted security rhetoric despite frequent discussion. Second, security emphasis rises over time in every parliament studied. Third, highly securitized debates cluster around the topics of transitions to quantum-secure communication infrastructures, great-power competition and alliances (including AUKUS), and the regulation of cross-border capital, knowledge, and technology flows. The study contributes cross-national, longitudinal evidence on how quantum technologies are politicized.

Variational Quantum Eigensolver (VQE) is widely used in near-term hardware. However, their performances remain limited by the poor trainability and are dependent on random parameter initialization. In this work, we propose a warm start method inspired by imaginary time evolution, allowing for determining initial parameters that prioritize lower energy states in a resource-efficient way. Using classical simulations, we demonstrate that this warm start method significantly improves the success rate and reduces the number of iterations required for the convergence of VQE. The numerical results also indicate that the warm start approach effectively mitigates statistical errors arising from a finite number of measurements, and to a certain extent alleviates the effect of barren plateaus.

The rapid growth of quantum information science and technology (QIST) presents unique educational challenges as it brings together students and researchers from many disciplines. This work presents findings from in-depth interviews with leading quantum researchers who are also educators, whose perspectives provide guidance for developing a framework for interdisciplinary QIST teaching and builds on our earlier paper that focused on QIST courses and curricula. We discuss quantum educators’ reflections on three critical aspects of QIST education: (1) the development of a common interdisciplinary language, (2) determining appropriate levels of abstraction and physical detail for diverse student populations from various disciplines, and (3) why students should pursue courses, degrees, and careers in this rapidly evolving field. Our analysis reveals that the emergence of linguistic evolutions such as “qubits” and “measurement bases”, rather than a focus on measurement of physical observables and their corresponding Hermitian operators, has begun to create a unifying framework that transcends disciplinary boundaries. Nevertheless, educators face ongoing challenges in balancing the level of abstractness with physical details as well as mathematical rigor with conceptual accessibility, particularly when teaching foundational QIST courses to an interdisciplinary group of students. The experts emphasize that successful QIST education for an interdisciplinary student body not only requires a shift from traditional quantum mechanics pedagogy for physics majors, but careful consideration of students’ diverse prior conceptual and mathematical foundations overall. They encourage students to pursue QIST related courses, degrees, and careers, highlighting the unique historical opportunity to participate in creating transformative quantum technologies while developing transferable skills for an evolving technological landscape. These findings provide valuable guidance for developing a framework for interdisciplinary QIST teaching especially useful for foundational courses.

This study explores the implementation of the Quantum Approximate Optimisation Algorithm (QAOA) in its analog form using a neutral atom quantum processing unit to solve the Maximum Independent Set problem. Our QAOA protocol leverages the natural encoding of problem Hamiltonians by Rydberg atom interactions, while employing Bayesian Optimisation to navigate the quantum-classical parameter space effectively under the constraints of hardware noise and resource limitations. We evaluate the approach through a combination of numerical simulations and experimental runs on Pasqal’s first commercial quantum processing unit, Orion Alpha, demonstrating effective parameter optimisation and noise mitigation strategies, such as selective bitstring discarding and detection error corrections. Results show that a limited number of measurements still allows for a quick convergence to a solution, making it a viable solution for resource-efficient scenarios.

Quantum Monte Carlo integration (QMCI), a quantum algorithm for calculating expectations that provides a quadratic speed-up compared to its classical counterpart, is now attracting increasing interest in the context of its industrial and scientific applications. In this paper, we propose the first application of QMCI to solving McKean-Vlasov stochastic differential equations (MVSDEs), a nonlinear class of SDEs whose drift and diffusion coefficients depend on the law (mu _{t}) of the solution (X_{t})—appearing in fields such as finance and fluid mechanics. We focus on the problem setting where the coefficients depend on (mu _{t}) through expectations of some functions (mathbb{E}[varphi _{k}(X_{t})]), and the goal is to compute the expectation of a function (mathbb{E}[phi (X_{T})]) at a terminal time T. We devise a quantum algorithm that leverages QMCI to compute these expectations, combined with a high-order time discretization method for SDEs and extrapolation of the expectations in time. The proposed algorithm estimates (mathbb{E}[phi (X_{T})]) with accuracy ϵ, making (O(1/epsilon ^{1+2/p})) queries to the quantum circuit for time evolution over one step, where (pin (1,2]) is the weak order of the SDE discretization method. This demonstrates the speed-up over the well-known classical algorithm called the particle method with complexity of (O(1/epsilon ^{3})). We conduct numerical demonstrations of our quantum algorithm applied to examples of MVSDEs, with some parts emulated classically, and observe that the accuracy and complexity behave as expected.

Quantum computing is gaining strategic relevance beyond research-driven industries. However, many companies lack the expertise to evaluate its potential for real-world applications. Traditional training formats often focus on physical principles without demonstrating practical relevance for their Business Processes, which limits success.

This paper presents a user-centered workshop concept tailored to IT professionals without prior quantum knowledge. Using a business simulation game set in a fictitious company, participants explore quantum technologies through relatable, application-driven scenarios. The flexible design allows customization for different organizational contexts.

Evaluation results from a one-day implementation at the IT-Tage 2024 indicate clear learning progress and increased awareness of practical use cases. The approach effectively bridges the gap between complex quantum concepts and industry-specific application needs.