EPJ Quantum Technology最新文献_第5页

Continuous variable entanglement between propagating optical modes using optomechanics 利用光力学实现传播光模式之间的连续可变纠缠

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-06-20 DOI: 10.1140/epjqt/s40507-024-00252-y

Greeshma Gopinath, Yong Li, Sankar Davuluri

引用次数: 0

An intelligent threshold selection method to improve orbital angular momentum-encoded quantum key distribution under turbulence 改进湍流条件下轨道角动量编码量子密钥分发的智能阈值选择方法

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-06-06 DOI: 10.1140/epjqt/s40507-024-00251-z

Jia-Hao Li, Jie Tang, Xing-Yu Wang, Yang Xue, Hui-Cun Yu, Zhi-Feng Deng, Yue-Xiang Cao, Ying Liu, Dan Wu, Hao-Ran Hu, Ya Wang, Hua-Zhi Lun, Jia-Hua Wei, Bo Zhang, Bo Liu, Lei Shi

{"title":"An intelligent threshold selection method to improve orbital angular momentum-encoded quantum key distribution under turbulence","authors":"Jia-Hao Li, Jie Tang, Xing-Yu Wang, Yang Xue, Hui-Cun Yu, Zhi-Feng Deng, Yue-Xiang Cao, Ying Liu, Dan Wu, Hao-Ran Hu, Ya Wang, Hua-Zhi Lun, Jia-Hua Wei, Bo Zhang, Bo Liu, Lei Shi","doi":"10.1140/epjqt/s40507-024-00251-z","DOIUrl":"10.1140/epjqt/s40507-024-00251-z","url":null,"abstract":"<div><p>High-dimensional quantum key distribution (HD-QKD) encoded by orbital angular momentum (OAM) presents significant advantages in terms of information capacity. However, perturbations caused by free-space atmospheric turbulence decrease the performance of the system by introducing random fluctuations in the transmittance of OAM photons. Currently, the theoretical performance analysis of OAM-encoded QKD systems exists a gap when concerning the statistical distribution under the free-space link. In this article, we analyzed the security of QKD systems by combining probability distribution of transmission coefficient (PDTC) of OAM with decoy-state BB84 method. To address the problem that the invalid key rate is calculated in the part transmittance interval of the post-processing process, an intelligent threshold method based on neural network is proposed to improve OAM-encoded QKD, which aims to conserve computing resources and enhance system efficiency. Our findings reveal that the ratio of root mean square (RMS) OAM-beam radius to Fried constant plays a crucial role in ensuring secure key generation. Meanwhile, the training error of neural network is at the magnitude around 10<sup>−3</sup>, indicating the ability to predict optimization parameters quickly and accurately. Our work contributes to the advancement of parameter optimization and prediction for free-space OAM-encoded HD-QKD systems. Furthermore, it provides valuable theoretical insights to support the development of free-space experimental setups.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00251-z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141264543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Towards quantum technologies with gamma photons 利用伽马光子发展量子技术

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-06-06 DOI: 10.1140/epjqt/s40507-024-00240-2

S. Ujeniuc, R. Suvaila

{"title":"Towards quantum technologies with gamma photons","authors":"S. Ujeniuc, R. Suvaila","doi":"10.1140/epjqt/s40507-024-00240-2","DOIUrl":"10.1140/epjqt/s40507-024-00240-2","url":null,"abstract":"<div><p>In the context of the second quantum revolution, the ability to manipulate quantum systems is already used for various techniques and a growing number of technology demonstrators, mostly with low energy photons. In this frame, our intention is to extend quantum technologies to gamma photons. Our aim is to take advantage of resources brought by entanglement with higher energy particles, particularly electron-positron annihilation quanta. Tools for low frequency quantum experiments are not suitable for penetrant radiation, consequently we need to use effects typical to the keV-MeV energy range instead. High energy photon protocols would include fundamental properties testing, industrial imaging, quantum random number generators, quantum simulators, military applications and improvement of already existing medical procedures. In this paper we review some important steps in the study of annihilation photon correlations, we point out the experimental differences and necessities with respect to the energy increase in quantum photonic experiments and we describe the design of a quantum gamma device we propose for experiments meant to prove feasibility of gamma ray based protocols. The perspective behind our project is to evidence the possibility to communicate via entangled quanta through media which are not transparent for low energy photons.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00240-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141264544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A KPI framework to standardize the measurement of a country’s progress in bringing quantum computing into application 量子计算应用进展的标准化衡量指标框架

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-06-04 DOI: 10.1140/epjqt/s40507-024-00245-x

Quantum Technology and Application Consortium – QUTAC, Julia Binder, Lara Hachmann, Sebastian Luber

{"title":"A KPI framework to standardize the measurement of a country’s progress in bringing quantum computing into application","authors":"Quantum Technology and Application Consortium – QUTAC, Julia Binder, Lara Hachmann, Sebastian Luber","doi":"10.1140/epjqt/s40507-024-00245-x","DOIUrl":"10.1140/epjqt/s40507-024-00245-x","url":null,"abstract":"<div><p>Quantum computing (QC) is a new and disruptive technology with large economic potential especially in application and downstream value creation stages. Hence, it is important for an economy to understand the current implementation state and to know the ecosystem to support the successful industrial application of this technology. Regularly identifying potential areas of improvement and then defining appropriate actions is necessary to ensure a leading position. Therefore, the Quantum Technology and Application Consortium (QUTAC) has developed a Key Performance Indicator (KPI) framework consisting of 24 KPIs that represent a country’s performance in applying QC. Detailed measurement guidelines and clear data sources ensure transparency of measurement, reproducibility of KPI values and comparability over time. An aggregation method allows summarizing the results of all KPIs. Thus, it is possible to assess the performance of each stakeholder involved and to calculate a single composite indicator that represents the country’s performance. The KPI framework can be adapted to any country and enables the comparison of the performance of different countries. It is a proposal for standardizing the evaluation of QC and its ecosystem on a national level. Thus, strengths and weaknesses can be identified and measurements for improvement derived. The paper highlights the development of the framework, its main features and the application of the framework to Germany. Based on the results, we will discuss the current state of QC application in Germany and make possible suggestions for improvement.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00245-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141251241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis of robust memory modes for linear quantum systems with unknown inputs 合成具有未知输入的线性量子系统的稳健记忆模式

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-05-30 DOI: 10.1140/epjqt/s40507-024-00249-7

Zibo Miao, Xinpeng Chen, Yu Pan, Qing Gao

{"title":"Synthesis of robust memory modes for linear quantum systems with unknown inputs","authors":"Zibo Miao, Xinpeng Chen, Yu Pan, Qing Gao","doi":"10.1140/epjqt/s40507-024-00249-7","DOIUrl":"10.1140/epjqt/s40507-024-00249-7","url":null,"abstract":"<div><p>In this paper, the synthesis of robust memory modes for linear quantum passive systems in the presence of unknown inputs has been studied, aimed at facilitating secure storage and communication of quantum information. In particular, we can switch on decoherence-free (DF) modes in the storage stage by placing the poles on the imaginary axis via a coherent feedback control scheme, and these memory modes can further be simultaneously made robust against perturbations to the system parameters by minimizing the condition number associated with imaginary poles. The DF modes can also be switched off by tuning the controller parameters to place the poles in the left half of the complex plane in the writing/reading stage. We develop explicit algebraic conditions guiding the design of such a coherent quantum controller, which involves employing an augmented system model to counter the influence of unknown inputs. Examples are provided to illustrate the procedure of synthesizing robust memory modes for linear optical quantum systems.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00249-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141182087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Full quantum tomography study of Google’s Sycamore gate on IBM’s quantum computers 在 IBM 量子计算机上对谷歌梧桐门进行全量子层析研究

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-05-27 DOI: 10.1140/epjqt/s40507-024-00248-8

Muhammad AbuGhanem, Hichem Eleuch

{"title":"Full quantum tomography study of Google’s Sycamore gate on IBM’s quantum computers","authors":"Muhammad AbuGhanem, Hichem Eleuch","doi":"10.1140/epjqt/s40507-024-00248-8","DOIUrl":"10.1140/epjqt/s40507-024-00248-8","url":null,"abstract":"<div><p>The potential of achieving computational hardware with quantum advantage depends heavily on the quality of quantum gate operations. However, the presence of imperfect two-qubit gates poses a significant challenge and acts as a major obstacle in developing scalable quantum information processors. Google’s Quantum AI and collaborators claimed to have conducted a supremacy regime experiment. In this experiment, a new two-qubit universal gate called the <i>Sycamore</i> gate is constructed and employed to generate random quantum circuits (RQCs), using a programmable quantum processor with 53 qubits. These computations were carried out in a computational state space of size <span>(9 times 10^{15})</span>. Nevertheless, even in strictly-controlled laboratory settings, quantum information on quantum processors is susceptible to various disturbances, including undesired interaction with the surroundings and imperfections in the quantum state. To address this issue, we conduct both quantum state tomography (QST) and quantum process tomography (QPT) experiments on Google’s <i>Sycamore</i> gate using different artificial architectural superconducting quantum computer. Furthermore, to demonstrate how errors affect gate fidelity at the level of quantum circuits, we design and conduct full QST experiments for the five-qubit eight-cycle circuit, which was introduced as an example of the programability of Google’s <i>Sycamore</i> quantum processor. These quantum tomography experiments are conducted in three distinct environments: noise-free, noisy simulation, and on IBM Quantum’s genuine quantum computer. Our results offer valuable insights into the performance of IBM Quantum’s hardware and the robustness of <i>Sycamore</i> gates within this experimental setup. These findings contribute to our understanding of quantum hardware performance and provide valuable information for optimizing quantum algorithms for practical applications.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00248-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141156455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Different secure semi-quantum summation models without measurement 无需测量的不同安全半量子求和模型

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-05-22 DOI: 10.1140/epjqt/s40507-024-00247-9

Yuan Tian, Nanyijia Zhang, Chongqiang Ye, Genqing Bian, Jian Li

引用次数: 0

Holonomic swap and controlled-swap gates of neutral atoms via selective Rydberg pumping 通过选择性雷德贝格泵浦实现中性原子的整体交换和受控交换门

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-05-21 DOI: 10.1140/epjqt/s40507-024-00246-w

C. F. Sun, X. Y. Chen, W. L. Mu, G. C. Wang, J. B. You, X. Q. Shao

引用次数: 0

Spooky action at a distance? A two-phase study into learners’ views of quantum entanglement 超距作用？分两个阶段研究学习者对量子纠缠的看法

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-05-10 DOI: 10.1140/epjqt/s40507-024-00244-y

Michael Brang, Helena Franke, Franziska Greinert, Malte S. Ubben, Fabian Hennig, Philipp Bitzenbauer

{"title":"Spooky action at a distance? A two-phase study into learners’ views of quantum entanglement","authors":"Michael Brang, Helena Franke, Franziska Greinert, Malte S. Ubben, Fabian Hennig, Philipp Bitzenbauer","doi":"10.1140/epjqt/s40507-024-00244-y","DOIUrl":"10.1140/epjqt/s40507-024-00244-y","url":null,"abstract":"<div><p>Quantum entanglement is a challenging concept within the field of physics education, often eluding a full grasp by both educators and learners alike. In this paper, we report findings from a two-phase empirical study into the views of entanglement held by pre-service physics teachers and physics students from various universities. In the first phase, we utilized a questionnaire consisting of open-ended questions which was completed by 31 pre-service physics teachers. The study participants’ ideas were explored using qualitative content analysis which led to the creation of rating scale items used in study phase 2. These items were administered to a broader cohort including 73 physics university students in order to capture the learners’ agreement or disagreement with the questionnaire statements, and hence, helped to validate and substantiate the in-depth insights from study phase 1. Key findings revealed widespread accurate notions, like the need to consider the entire system when examining entangled states. However, less elaborated views were also identified, including ideas such as that measurements of entangled states always show perfect (anti-)correlation. Another striking observation was the confusion between quantum entanglement and superposition. In the case of quantum teleportation, many participants seemed to have a basic grasp of the concept, although a number of misconceptions were apparent, notably the idea that quantum entanglement enables faster-than-light communication. Practically, the findings can assist educators in anticipating and addressing widespread (mis-)conceptions, paving the way for more effective instruction in quantum mechanics and its real-world applications, such as quantum cryptography and computing.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00244-y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140902650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On-premises superconducting quantum computer for education and research 用于教育和研究的内部超导量子计算机

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-04-29 DOI: 10.1140/epjqt/s40507-024-00243-z

Jami Rönkkö, Olli Ahonen, Ville Bergholm, Alessio Calzona, Attila Geresdi, Hermanni Heimonen, Johannes Heinsoo, Vladimir Milchakov, Stefan Pogorzalek, Matthew Sarsby, Mykhailo Savytskyi, Stefan Seegerer, Fedor Šimkovic IV, P. V. Sriluckshmy, Panu T. Vesanen, Mikio Nakahara

引用次数: 0