Advanced quantum technologies最新文献

{"title":"Front Cover: Positional Accuracy of 3D Printed Quantum Emitter Fiber Couplers (Adv. Quantum Technol. 11/2024)","authors":"Ksenia Weber,&nbsp;Simon Thiele,&nbsp;Mario Hentschel,&nbsp;Alois Herkommer,&nbsp;Harald Giessen","doi":"10.1002/qute.202470031","DOIUrl":"https://doi.org/10.1002/qute.202470031","url":null,"abstract":"<p>The cover image depicts coupling of the light emission of single quantum emitters to single mode fibers. 3D printed microoptics are used to create the aspheric optics that matches the numerical apertures of light emission cone and fibers to each other. Additionally, a 3D printed chuck is used to place the fiber in the correct distance and with the correct horizontal alignment over the quantum emitters. The article by Harald Giessen and co-workers (article number 2400135) describes the quantification of the alignment accuracy and reproducibility of such 3D printed couplers. [Cover image: © Florian Sterl, Sterltech Optics.]\u0000\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"7 11","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202470031","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Back Cover: Analysis for Satellite-Based High-Dimensional Extended B92 and High-Dimensional BB84 Quantum Key Distribution (Adv. Quantum Technol. 11/2024)","authors":"Arindam Dutta,&nbsp; Muskan,&nbsp;Subhashish Banerjee,&nbsp;Anirban Pathak","doi":"10.1002/qute.202470033","DOIUrl":"https://doi.org/10.1002/qute.202470033","url":null,"abstract":"<p>In article number 2400149, Arindam Dutta and co-workers study the implementation of high-dimensional quantum key distribution protocols, HD-Ext-B92 and HD-BB84, via satellite. The study modifies key rate calculations to explore variations in key rate, probability distribution, and quantum bit error rate (QBER) with respect to dimension and noise. The research examines how the average key rate changes with zenith angle and link length under different weather conditions, showing HD-BB84's superior performance in higher dimensions despite higher QBER saturation. The down-link configuration is shown to be preferable over the up-link configuration.\u0000\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"7 11","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202470033","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Issue Information (Adv. Quantum Technol. 11/2024)","authors":"","doi":"10.1002/qute.202470034","DOIUrl":"https://doi.org/10.1002/qute.202470034","url":null,"abstract":"","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"7 11","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202470034","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical Dynamics Around Higher-Order Exceptional Point in Magno-Optomechanics","authors":"Wen-Di He,&nbsp;Xiao-Hong Fan,&nbsp;Ming-Yue Liu,&nbsp;Guo-Qiang Zhang,&nbsp;Hai-Chao Li,&nbsp;Wei Xiong","doi":"10.1002/qute.202400275","DOIUrl":"https://doi.org/10.1002/qute.202400275","url":null,"abstract":"<p>Diverse exceptional points (EPs) are theoretically studied in an experimentally feasible magno-optomechanics consisting of an optomechanical subsystem coupled to a magnomechanical subsystem via physically direct contact. By adiabatically eliminating both the cavity and the Kittel mode, dissipative and parity-time symmetric exceptional points can be observed. When only the cavity mode is eliminated, a second (third)-order pseudo-Hermitian EP emerges for nondegenerate (degenerate) mechanical modes. The distinct dynamical behavior of two mechanical modes around these EPs are further studied. The proposal provides a promising way to engineer diverse EPs and quantify non-Hermitian phase transition with exceptional dynamical behavior in magno-optomechanics.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 3","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multidimensional Quantum Generative Modeling by Quantum Hartley Transform","authors":"Hsin-Yu Wu,&nbsp;Vincent E. Elfving,&nbsp;Oleksandr Kyriienko","doi":"10.1002/qute.202400337","DOIUrl":"https://doi.org/10.1002/qute.202400337","url":null,"abstract":"<p>An approach for building quantum models based on the exponentially growing orthonormal basis of Hartley kernel functions is developed. First, a differentiable Hartley feature map parameterized by real-valued argument that enables quantum models suitable for solving stochastic differential equations and regression problems is designed. Unlike the naturally complex Fourier encoding, the proposed Hartley feature map circuit leads to quantum states with real-valued amplitudes, introducing an inductive bias and natural regularization. Next, a quantum Hartley transform circuit is proposed as a map between computational and Hartley basis. The developed paradigm is applied to generative modeling from solutions of stochastic differential equations, and utilize the quantum Hartley transform for fine sampling from parameterized distributions through an extended register. Finally, the capability of multivariate quantum generative modeling is demonstrated for both correlated and uncorrelated distributions. As a result, the developed quantum Hartley-based generative models (QHGMs) offer a distinct quantum approach to generative AI at increasing scale.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 3","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202400337","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Witnessing Entanglement and Quantum Correlations in Condensed Matter: A Review","authors":"Pontus Laurell,&nbsp;Allen Scheie,&nbsp;Elbio Dagotto,&nbsp;D. Alan Tennant","doi":"10.1002/qute.202400196","DOIUrl":"https://doi.org/10.1002/qute.202400196","url":null,"abstract":"<p>The detection and certification of entanglement and quantum correlations in materials is of fundamental and far-reaching importance, and has seen significant recent progress. It impacts both the understanding of the basic science of quantum many-body phenomena as well as the identification of systems suitable for novel technologies. Frameworks suitable to condensed matter that connect measurements to entanglement and coherence have been developed in the context of quantum information theory. These take the form of entanglement witnesses and quantum correlation measures.</p><p>The underlying theory of these quantities, their relation to condensed matter experimental techniques, and their application to real materials are comprehensively reviewed. In addition, their usage in, e.g., protocols, the relative advantages and disadvantages of witnesses and measures, and future prospects in, e.g., correlated electrons, entanglement dynamics, and entangled spectroscopic probes, are presented. Consideration is given to the interdisciplinary nature of this emerging research and substantial ongoing progress by providing an accessible and practical treatment from fundamentals to application. Particular emphasis is placed on quantities accessible to collective measurements, including by susceptibility and spectroscopic techniques. This includes the magnetic susceptibility witness, one-tangle, concurrence and two-tangle, two-site quantum discord, and quantum coherence measures such as the quantum Fisher information.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 3","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202400196","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Engineering Epitaxial Interfaces for Topological Insulator — Superconductor Hybrid Devices with Al Electrodes","authors":"Abdur Rehman Jalil,&nbsp;Tobias W. Schmitt,&nbsp;Philipp Rüßmann,&nbsp;Xian-Kui Wei,&nbsp;Benedikt Frohn,&nbsp;Michael Schleenvoigt,&nbsp;Wilhelm Wittl,&nbsp;Xiao Hou,&nbsp;Anne Schmidt,&nbsp;Kaycee Underwood,&nbsp;Gustav Bihlmayer,&nbsp;Martina Luysberg,&nbsp;Joachim Mayer,&nbsp;Stefan Blügel,&nbsp;Detlev Grützmacher,&nbsp;Peter Schüffelgen","doi":"10.1002/qute.202400343","DOIUrl":"https://doi.org/10.1002/qute.202400343","url":null,"abstract":"<p>Proximity-induced superconductivity in hybrid devices of topological insulators and superconductors offers a promising platform for the pursuit of elusive topological superconductivity and its anticipated applications, such as fault-tolerant quantum computing. To study and harness such hybrid devices, a key challenge is the realization of highly functional material interfaces with a suitable superconductor featuring 2<span></span><math>\u0000 <semantics>\u0000 <mi>e</mi>\u0000 <annotation>$e$</annotation>\u0000 </semantics></math>-periodic parity-conserving transport to ensure a superconducting hard-gap free of unpaired electrons, which is important for Majorana physics. A superconductor well-known for this characteristic is Al, however, its direct integration into devices based on tetradymite topological insulators has so far been found to yield non-transparent interfaces. By focusing on Bi₂Te₃-Al heterostructures, this study identifies detrimental interdiffusion processes at the interface through atomically resolved structural and chemical analysis, and showcases their mitigation by leveraging different interlayers – namely Nb, Ti, Pd, and Pt – between Bi₂Te₃ and Al. Through structural transformation of the interlayer materials (X) into their respective tellurides (XTe₂) atomically-sharp epitaxial interfaces are engineered and further characterized in low-temperature transport experiments on Al-X-Bi₂Te₃-X-Al Josephson junctions and in complementary density functional theory calculations. By demonstrating functional interfaces between Bi₂Te₃ and Al, this work provides key insights and paves the way for the next generation of sophisticated topological devices.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 3","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202400343","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Discrete and Parallel Frequency-Bin Entanglement Generation from Quantum Frequency Comb","authors":"Chi Lu,&nbsp;Xiaoyu Wu,&nbsp;Wenjun Wen,&nbsp;Xiao-song Ma","doi":"10.1002/qute.202400229","DOIUrl":"https://doi.org/10.1002/qute.202400229","url":null,"abstract":"<p>Photons’ frequency degree of freedom is promising to realize large-scale quantum information processing. Quantum frequency combs (QFCs) generated in integrated nonlinear microresonators can produce multiple frequency modes with narrow linewidth. Here, polarization-entangled QFCs are utilized to generate discrete frequency-bin entangled states. Fourteen pairs of polarization-entangled photons with different frequencies are simultaneously transformed into frequency-bin entangled states. The characteristic of frequency-bin entanglement is demonstrated by Hong-Ou-Mandel interference, which can be performed with single or multiple frequency pairs in parallel. This work paves the way for harnessing large-scale frequency-bin entanglement and converting between different degrees of freedom in quantum information processing.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 3","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wavelength Stabilization of Entangled Biphotons Using Dynamic Temperature Compensation for Quantum Interference Applications","authors":"Yuting Liu,&nbsp;Huibo Hong,&nbsp;Xiao Xiang,&nbsp;Runai Quan,&nbsp;Xinghua Li,&nbsp;Tao Liu,&nbsp;Mingtao Cao,&nbsp;Shougang Zhang,&nbsp;Ruifang Dong","doi":"10.1002/qute.202400305","DOIUrl":"https://doi.org/10.1002/qute.202400305","url":null,"abstract":"<p>In this paper, a dynamic temperature compensation method is presented to stabilize the wavelength of the entangled biphoton source, which is generated on spontaneous parametric down-conversion from a magnesium oxide doped periodically poled lithium niobate waveguide. Utilizing the dispersive Fourier transformation technique, the photon wavelength variation is monitored in case of conventional static temperature control, revealing a long-term wavelength drift up to 556.8 pm over a 14-h measurement period. A Hong-Ou-Mandel (HOM) interferometer is constructed to assess the impact on quantum applications, showing a decrease in visibility from 95.5% to 69.4%. To address this issue, a digital proportional-integral-differential algorithm is implemented to dynamically compensate the working temperature variation of the waveguide, thereby instantly stabilizing the wavelength to a peak-to-peak fluctuation of +138.05 pm/-127.61 pm with the standard deviation being 30.49 pm. The wavelength stability shows more than a hundredfold enhancement in terms of Allan deviation, reaching <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>1.67</mn>\u0000 <mo>×</mo>\u0000 <msup>\u0000 <mn>10</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>7</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation>$1.67 times {{10}^{ - 7}}$</annotation>\u0000 </semantics></math> at an averaging time of 10000 s. With the dynamic control in operation, the HOM interference visibility turns to stable at 96.1% ± 0.6%. The method provides a simple and accessible solution for precisely controlling and stabilizing the wavelength of entangled biphotons, thus improving performance in various quantum information processing applications.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 3","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction to Topological Properties of a Non-Hermitian Quasi-1D Chain with a Flat Band","authors":"","doi":"10.1002/qute.202400348","DOIUrl":"https://doi.org/10.1002/qute.202400348","url":null,"abstract":"<p>C. Martínez-Strasser, M. A. J. Herrera, A. García-Etxarri, G. Palumbo, F. K. Kunst, D. Bercioux, Topological Properties of a Non-Hermitian Quasi-1D Chain with a Flat Band. <i>Adv Quantum Technol</i>. <b>2024</b>, <i>7</i>, 2300225.</p><p>In this correction to the article titled “Topological Properties of a Non-Hermitian Quasi-1D Chain with a Flat Band” we show that the previously claimed non-Hermitian skin effect found in the non-Hermitian diamond chain in configuration B (DCB) is mistaken. The observed accumulation of the eigenstates towards the edges in the representation used in Figure 5 results from an incorrect selection of the basis for the flat band eigenstates in the <i>Wolfram Language</i> (WL).</p><p>In general, states in the flat bands are defined as a linear combination of compact localized states (CLSs). However, the WL is unable to determine this basis. As a result, summing the squared amplitudes on each site leads to an accumulation that appears to increase in weight towards the boundaries (see Figure A(a)). Whereas a correct CLS base does not induce this accumulation - see Figure A(b).</p><p>As a result, Figure 5 and Figure 9 are incorrect. Replacement figures are shown in Figures B and D, respectively, below.</p><p>Additionally, Figure D shows the correct representation of the sum of amplitudes at each site of the rotated DCB model presenting real non-reciprocal couplings (refer to Figure 8b in the article). In this model, the right and left eigenvectors are identical. Notably, this model does not exhibit the non-Hermitian skin effect, neither on the sites producing the flat band nor on the Hermitian SSH chain coupled in a non-Hermitian fashion to the flat band sites (see Figure E).</p><p>The authors acknowledge useful discussions with Julius Gohsrich for giving insight to this matter.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 3","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202400348","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}