EPJ Quantum Technology最新文献_第6页

Quantum image representations based on density matrices in open quantum systems 开放量子系统中基于密度矩阵的量子图像表征

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-04-19 DOI: 10.1140/epjqt/s40507-024-00241-1

Yingying Hu, Dayong Lu, Qianqian Zhang, Meiyu Xu

{"title":"Quantum image representations based on density matrices in open quantum systems","authors":"Yingying Hu, Dayong Lu, Qianqian Zhang, Meiyu Xu","doi":"10.1140/epjqt/s40507-024-00241-1","DOIUrl":"10.1140/epjqt/s40507-024-00241-1","url":null,"abstract":"<div><p>So far, research on quantum image representation has gone through more than 20 years. During this time, the quantum image representation models used have almost all been based on state vectors. However, in practical problems, the environment and the principal quantum system cannot be separated, and isolated quantum systems do not exist in principle. This case is often referred to as an open quantum system. In open quantum systems, many problems involve density matrices, such as the calculation of Von Neumann entropy, the quantization of coherence, and the operator-sum representations of quantum operations. Therefore, the existing quantum image representation models are only suitable for closed quantum systems. To this end, the paper proposes three models that can not only represent quantum images in an open quantum system but also decompose the evolution process of quantum images utilizing operator-sum decomposition. These three models are the representation model of quantum gray-scale images, the tensor product representation model of quantum color images, and the representation model of quantum color images based on mixed states in the Bloch sphere, respectively. All these image representation models have strong correlations among them and are very different from their classical analogues. Between them, the biggest difference is that the paper employs density matrices, inspired by incoherent-coherent states, to represent quantum images rather than classical state vectors. By means of one of the representation models proposed in the paper, we finally demonstrate the evolution process of the quantum image going through the amplitude damping channel.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00241-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140619689","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

Efficient excitation-transfer across fully connected networks via local-energy optimization 通过局部能量优化实现全连接网络的高效激励传输

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-04-19 DOI: 10.1140/epjqt/s40507-024-00238-w

S. Sgroi, G. Zicari, A. Imparato, M. Paternostro

{"title":"Efficient excitation-transfer across fully connected networks via local-energy optimization","authors":"S. Sgroi, G. Zicari, A. Imparato, M. Paternostro","doi":"10.1140/epjqt/s40507-024-00238-w","DOIUrl":"10.1140/epjqt/s40507-024-00238-w","url":null,"abstract":"<div><p>We study the excitation transfer across a fully connected quantum network whose sites energies can be artificially designed. Starting from a simplified model of a broadly-studied physical system, we systematically optimize its local energies to achieve high excitation transfer for various environmental conditions, using an adaptive Gradient Descent technique and Automatic Differentiation. We show that almost perfect transfer can be achieved with and without local dephasing, provided that the dephasing rates are not too large. We investigate our solutions in terms of resilience against variations in either the network connection strengths, or size, as well as coherence losses. We highlight the different features of a dephasing-free and dephasing-driven transfer. Our work gives further insight into the interplay between coherence and dephasing effects in excitation-transfer phenomena across fully connected quantum networks. In turn, this will help designing optimal transfer in artificial open networks through the simple manipulation of local energies.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00238-w","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140619690","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

The core of secondary level quantum education: a multi-stakeholder perspective 中学量子教育的核心：多方利益相关者的视角

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-04-08 DOI: 10.1140/epjqt/s40507-024-00237-x

Avraham Merzel, Philipp Bitzenbauer, Kim Krijtenburg-Lewerissa, Kirsten Stadermann, Erica Andreotti, Daria Anttila, Maria Bondani, Maria Luisa (Marilù) Chiofalo, Sergej Faletič, Renaat Frans, Simon Goorney, Franziska Greinert, Leon Jurčić, Zdeňka Koupilová, Massimiliano Malgieri, Rainer Müller, Pasquale Onorato, Gesche Pospiech, Malte Ubben, Andreas Woitzik, Henk Pol

{"title":"The core of secondary level quantum education: a multi-stakeholder perspective","authors":"Avraham Merzel, Philipp Bitzenbauer, Kim Krijtenburg-Lewerissa, Kirsten Stadermann, Erica Andreotti, Daria Anttila, Maria Bondani, Maria Luisa (Marilù) Chiofalo, Sergej Faletič, Renaat Frans, Simon Goorney, Franziska Greinert, Leon Jurčić, Zdeňka Koupilová, Massimiliano Malgieri, Rainer Müller, Pasquale Onorato, Gesche Pospiech, Malte Ubben, Andreas Woitzik, Henk Pol","doi":"10.1140/epjqt/s40507-024-00237-x","DOIUrl":"10.1140/epjqt/s40507-024-00237-x","url":null,"abstract":"<div><p>Quantum physics (QP) education at the secondary school level is still in its infancy. Not only is there ongoing discussion about how to teach this subject, but there is also a lack of coherence in the selection of concepts to be taught, both across countries and over time. To contribute to this discussion, we investigated the perspectives of <span>(N= 39)</span> high school teachers, university-level physics educators, and physics education researchers regarding the essential concepts in QP and the corresponding illustrations that should be introduced at the secondary school level. We examined the prominence of different key concepts and illustrations, as well as the level of consensus among the various professional groups. Our analysis revealed that certain key concepts are universally valued across all professional groups, while others are specific to particular groups. Additionally, we explored the relationships between these key concepts and their corresponding illustrations. Overall, our study offers valuable insights into the perspectives of different stakeholders, emphasizing the essential concepts and visualizations that should be considered when designing and implementing the teaching of QP at the secondary school level.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00237-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140537485","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 quantum moving target segmentation algorithm for grayscale video based on background difference method 基于背景差分法的灰度视频量子移动目标分割算法

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-04-03 DOI: 10.1140/epjqt/s40507-024-00234-0

Lu Wang, Yuxiang Liu, Fanxu Meng, Wenjie Liu, Zaichen Zhang, Xutao Yu

{"title":"A quantum moving target segmentation algorithm for grayscale video based on background difference method","authors":"Lu Wang, Yuxiang Liu, Fanxu Meng, Wenjie Liu, Zaichen Zhang, Xutao Yu","doi":"10.1140/epjqt/s40507-024-00234-0","DOIUrl":"10.1140/epjqt/s40507-024-00234-0","url":null,"abstract":"<div><p>The classical moving target segmentation (MTS) algorithm in a video can segment the moving targets out by calculating frame by frame, but the algorithm encounters a real-time problem as the data increases. Recently, the benefits of quantum computing in video processing have been demonstrated, but it is still scarce for MTS. In this paper, a quantum moving target segmentation algorithm for grayscale video based on background difference method is proposed, which can simultaneously model the background of all frames and perform background difference to segment the moving targets. In addition, a feasible quantum subtractor is designed to perform the background difference operation. Then, several quantum units, including quantum cyclic shift transformation, quantum background modeling, quantum background difference, and quantum binarization, are designed in detail to establish the complete quantum circuit. For a video containing <span>(2^{m})</span> frames (every frame is a <span>(2^{n} times 2^{n})</span> image with <i>q</i> grayscale levels), the complexity of our algorithm is O<span>((n+q))</span>. This is an exponential speedup over the classical algorithm and also outperforms the existing quantum algorithms. Finally, the experiment on IBM Q demonstrates the feasibility of our algorithm in this noisy intermediate-scale quantum (NISQ) era.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00234-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140342895","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

Coulomb effect in hybrid double quantum dot-metal nanoparticle systems considering the wetting layer 考虑到润湿层的双量子点-金属纳米粒子混合系统中的库仑效应

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-03-26 DOI: 10.1140/epjqt/s40507-024-00233-1

Nour A. Nasser, Amin H. Al-Khursan

{"title":"Coulomb effect in hybrid double quantum dot-metal nanoparticle systems considering the wetting layer","authors":"Nour A. Nasser, Amin H. Al-Khursan","doi":"10.1140/epjqt/s40507-024-00233-1","DOIUrl":"10.1140/epjqt/s40507-024-00233-1","url":null,"abstract":"<div><p>Many body effects in the wetting layer (WL)-double quantum dot (DQD)-metal nanoparticle (MNP) structure have been studied by modeling the Coulomb scattering rates in this structure. The strong coupling between WL-DQD-MNPs was considered. An orthogonalized plane wave (OPW) is assumed between WL-QD transitions. The transition momenta are calculated accordingly to specify the normalized Rabi frequency on this structure, considering the strong coupling between the WL-DQD-MNP structures. This approach is important for realizing scattering rates, including in-and-out capture and relaxation rates, which are essential for specifying the type of structure used depending on the optimum value of the scattering time required to fit the application. The QD hole capture rate is the highest, and the hole capture times are the shortest. The relaxation times are less than the electron capture times by one order, while they are half of the hole capture times. The capture rates increase with increasing distance <i>R</i> between the DQDs and the MNP. High tunneling increases hole-capture rates and changes the relaxation rates, showing the importance of tunneling in controlling the scattering rates.</p></div>","PeriodicalId":547,"journal":{"name":"EPJ Quantum Technology","volume":"11 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://epjquantumtechnology.springeropen.com/counter/pdf/10.1140/epjqt/s40507-024-00233-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140297158","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

Quantum gate sets for lattice QCD in the strong-coupling limit: (N_{f}=1) 强耦合极限下格子 QCD 的量子门集：(N_{f}=1)

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-03-25 DOI: 10.1140/epjqt/s40507-024-00236-y

Michael Fromm, Owe Philipsen, Wolfgang Unger, Christopher Winterowd

引用次数: 0

Cryptanalysis and improvement of efficient multiparty quantum secret sharing based on a novel structure and single qubits 基于新型结构和单量子比特的高效多方量子秘密共享的密码分析与改进

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-03-25 DOI: 10.1140/epjqt/s40507-024-00235-z

Gan Gao

引用次数: 0

Local oscillator port integrated resonator for Rydberg atom-based electric field measurement enhancement 用于增强基于雷德贝格原子的电场测量的局域振荡器端口集成谐振器

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-03-22 DOI: 10.1140/epjqt/s40507-024-00231-3

Bo Wu, Dunwei Liao, Zhenke Ding, Kai Yang, Yi Liu, Di Sang, Qiang An, Yunqi Fu

引用次数: 0

Precise certification of a qubit space 量子比特空间的精确认证

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-03-19 DOI: 10.1140/epjqt/s40507-024-00230-4

Tomasz Białecki, Tomasz Rybotycki, Josep Batle, Jakub Tworzydło, Adam Bednorz

引用次数: 0

Simulating (Z_{2}) lattice gauge theory with the variational quantum thermalizer 用可变量子热化器模拟（Z_{2}）晶格规理论

IF 5.3 2区物理与天体物理

EPJ Quantum Technology Pub Date : 2024-03-15 DOI: 10.1140/epjqt/s40507-024-00232-2

Michael Fromm, Owe Philipsen, Michael Spannowsky, Christopher Winterowd

引用次数: 0