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Maximizing Big Data for Data-Driven Decision Making: An In-Depth Assessment

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Maximizing Big Data for Data-Driven Decision Making: An In-D...

Sustainable Computing and Integrated Communication in Changing Landscape of AI (ICSCAI), International Conference on

作者： Maneesh Kumar Dilrajpreet Kaur Akash Sanghi K. Yuvaraj C. Mukuntharaj Jayashree Tamkhade School of Engineering and Computer Dev Bhoomi Uttarakhand University Uttarakhand Department of Physics School of Basic & Applied Sciences K. R. Mangalam University Gurugram Haryana INDIA Department of Computer Science & Engineering Invertis University Bareilly Uttar Pradesh Department of Computer Science Karpagam Academy of Higher Education Coimbatore Department of Electronics and Communication Engineering Karpagam College of Engineering Coimbatore E&TC Vishwakarma Institute of Information Technology Pune

ISBN: (数字)9798350355338

ISBN: (纸本)9798350355345

In this essay, we examine the history and current condition. We begin by outlining the history of big information reviewing similar technologies including centers, and Hadoop. The four stages of the chain-data production, data capture, — are then the main emphasis. [1] We lay out the overall context, talk about the difficulties, and cover the most recent developments for each step. Finally, we look at a number of exemplary big business. These conversations are meant a thorough introduction and overall picture of this fascinating field. A discussion of unresolved issues and prospective directions follows this survey's conclusion.

关键词： Data privacy Data centers Decision making Oral communication Production Companies Big Data Smart grids History Internet of Things

Modeling the performance and bandwidth of single-atom adiabatic quantum memories

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arXiv 2023年

作者： Nateeboon, Takla Cholsuk, Chanaprom Vogl, Tobias Suwanna, Sujin Optical and Quantum Physics Laboratory Department of Physics Faculty of Science Mahidol University Bangkok10400 Thailand Department of Computer Engineering TUM School of Computation Information and Technology Technical University of Munich Munich80333 Germany Abbe Center of Photonics Institute of Applied Physics Friedrich Schiller University Jena07745 Germany

Quantum memories are essential for quantum repeaters that will form the backbone of the future quantum internet. Such memory can capture a signal state for a controllable amount of time after which this state can be retrieved. In this work, we theoretically investigated how atomic material and engineering parameters affect the performance and bandwidth of a quantum memory. We have applied a theoretical model for quantum memory operation based on the Lindblad master equation and adiabatic quantum state manipulation. The materials’ properties and their uncertainty are evaluated to determine the performance of Raman-type quantum memories by showcasing two defects in two-dimensional hexagonal boron nitride (hBN). We have derived a scheme to calculate the signal bandwidth based on the material parameters as well as the maximum efficiency that can be realized. The bandwidth depends on four factors: the signal photon frequency, the dipole transition moments in the electronic structure, cavity volume, and the strength of the external control electric field. As our scheme is general and independent of materials, it can be applied to many other quantum materials with a suitable three-level structure. We therefore provided a promising route for designing and selecting materials for quantum memories. Our work is therefore an important step toward the realization of a large-scale quantum network. Copyright © 2023, The Authors. All rights reserved.

关键词： Bandwidth

Identifying electronic transitions of defects in hexagonal boron nitride for quantum memories

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arXiv 2023年

作者： Cholsuk, Chanaprom Çakan, Aslı Suwanna, Sujin Vogl, Tobias Department of Computer Engineering School of Computation Information and Technology Technical University of Munich Munich80333 Germany Abbe Center of Photonics Institute of Applied Physics Friedrich Schiller University Jena Jena07745 Germany Optical and Quantum Physics Laboratory Department of Physics Faculty of Science Mahidol University Bangkok10400 Thailand

A quantum memory is a crucial keystone for enabling large-scale quantum networks. Applicable to the practical implementation, specific properties, i.e., long storage time, selective efficient coupling with other systems, and a high memory efficiency are desirable. Though many quantum memory systems are developed thus far, none of them can perfectly meet all requirements. This work herein proposes a quantum memory based on color centers in hexagonal boron nitride (hBN), where its performance is evaluated based on a simple theoretical model of suitable defects in a cavity. Employing density functional theory calculations, 257 triplet and 211 singlet spin electronic transitions are investigated. Among these defects, it is found that some defects inherit the Λ electronic structures desirable for a Raman-type quantum memory and optical transitions can couple with other quantum systems. Further, the required quality factor and bandwidth are examined for each defect to achieve a 95% writing efficiency. Both parameters are influenced by the radiative transition rate in the defect state. In addition, inheriting triplet-singlet spin multiplicity indicates the possibility of being a quantum sensing, in particular, optically detected magnetic resonance. This work therefore demonstrates the potential usage of hBN defects as a quantum memory in future quantum networks. Copyright © 2023, The Authors. All rights reserved.

关键词： Boron nitride

Ultrafast All-Optical Measurement of Squeezed Vacuum in a Lithium Niobate Nanophotonic Circuit

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arXiv 2025年

作者： Williams, James Sendonaris, Elina Nehra, Rajveer Gray, Robert M. Sekine, Ryoto Ledezma, Luis Marandi, Alireza Department of Electrical Engineering California Institute of Technology PasadenaCA91125 United States Department of Applied Physics California Institute of Technology PasadenaCA91125 United States Department of Electrical and Computer Engineering University of Massachusetts Amherst AmherstMA01003 United States Department of Physics University of Massachusetts Amherst AmherstMA01003 United States College of Information and Computer Science University of Massachusetts Amherst AmherstMA01003 United States

Squeezed vacuum, a fundamental resource for continuous-variable quantum information processing, has been used to demonstrate quantum advantages in sensing, communication, and computation. While most experiments use homodyne detection to characterize squeezing and are therefore limited to electronic bandwidths, recent experiments have shown optical parametric amplification (OPA) to be a viable measurement strategy. Here, we realize OPA-based quantum state tomography in integrated photonics and demonstrate the generation and all-optical Wigner tomography of squeezed vacuum in a nanophotonic circuit. We employ dispersion engineering to enable the distortion-free propagation of femtosecond pulses and achieve ultrabroad operation bandwidths, effectively lifting the speed restrictions imposed by traditional electronics on quantum measurements with a theoretical maximum clock speed of 6.5 THz. We implement our circuit on thin-film lithium niobate, a platform compatible with a wide variety of active and passive photonic components. Our results chart a course for realizing all-optical ultrafast quantum information processing in an integrated room-temperature platform. © 2025, CC BY-NC-ND.

关键词： Parametric amplifiers

Nonlocal Temporal Interferometry for Highly Resilient Free-Space Quantum Communication

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Physical Review X 2023年第2期13卷 021001-021001页

作者： Lukas Bulla Matej Pivoluska Kristian Hjorth Oskar Kohout Jan Lang Sebastian Ecker Sebastian P. Neumann Julius Bittermann Robert Kindler Marcus Huber Martin Bohmann Rupert Ursin Institute for Quantum Optics and Quantum Information (IQOQI) Austrian Academy of Sciences Boltzmanngasse 3 1090 Vienna Austria Vienna Center for Quantum Science and Technology (VCQ) Faculty of Physics University of Vienna Boltzmanngasse 5 1090 Vienna Austria Institute of Computer Science Masaryk University 602 00 Brno Czech Republic Institute of Physics Slovak Academy of Sciences 845 11 Bratislava Slovakia Department of Physics Faculty of Natural Sciences Norwegian University of Science and Technology (NTNU) NO-7491 Trondheim Norway Fraunhofer Institute for Applied Optics and Precision Engineering IOF Albert-Einstein-Strasse 7 07745 Jena Germany Friedrich-Schiller-Universitt Jena FSU Frstengraben 1 07743 Jena Germany Vienna Center for Quantum Science and Technology (VCQ) Atominstitut Technische Universität Wien Stadionallee 2 1020 Vienna Austria

Entanglement distribution via photons over long distances enables many applications, including quantum key distribution, which provides unprecedented privacy. The inevitable degradation of entanglement through noise accumulated over long distances remains one of the key challenges in this area. Exploiting the potential of higher-dimensional entangled photons promises to address this challenge, but poses extreme demands on the experimental implementation. Here, we present a long-range free-space quantum link, distributing entanglement over 10.2 km with flexible dimensionality of encoding by deploying a phase-stable nonlocal Franson interferometer. With this distribution of multidimensional energy-time entangled photons, we analyze the achievable key rate in a dimensionally adaptive quantum key distribution protocol that can be optimized with respect to any environmental noise conditions. Our approach enables and emphasizes the power of high-dimensional entanglement for quantum communication, yielding a positive asymptotic key rate well into the dawn of the day.

关键词： Quantum channels Quantum communication Quantum cryptography Quantum entanglement Quantum information theory Quantum networks

Photoinduced charge-carrier dynamics in a semiconductor-based ion trap investigated via motion-sensitive qubit transitions

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Physical Review A 2024年第4期109卷 043106-043106页

作者： Woojun Lee Daun Chung Honggi Jeon Beomgeun Cho KwangYeul Choi SeungWoo Yoo Changhyun Jung Junho Jeong Changsoon Kim Dong-Il “Dan” Cho Taehyun Kim Department of Computer Science and Engineering Seoul National University Seoul 08826 South Korea Automation and Systems Research Institute Seoul National University Seoul 08826 South Korea Institute of Computer Technology Seoul National University Seoul 08826 South Korea Inter-University Semiconductor Research Center Seoul National University Seoul 08826 South Korea Department of Electrical and Computer Engineering Seoul National University Seoul 08826 South Korea Department of Intelligence and Information Seoul National University Seoul 08826 South Korea Institute of Applied Physics Seoul National University Seoul 08826 South Korea

Ion trap systems built upon microfabricated chips have emerged as a promising platform for quantum computing to achieve reproducible and scalable structures. However, photoinduced charging of materials in such chips can generate undesired stray electric fields that disrupt the quantum state of the ion, limiting high-fidelity quantum control essential for practical quantum computing. While crude understanding of the phenomena has been gained heuristically over the past years, explanations for the microscopic mechanism of photogenerated charge carrier dynamics remains largely elusive. Here we present a photoinduced charging model for semiconductors, whose verification is enabled by a systematic interaction between trapped ions and photoinduced stray fields from exposed silicon surfaces in our chip. We use motion-sensitive qubit transitions to directly characterize the stray field and analyze its effect on the quantum dynamics of the trapped ion. In contrast to incoherent errors arising from the thermal motion of the ion, coherent errors are induced by the stray field, whose effect is significantly imprinted during the quantum control of the ion. These errors are investigated in depth, and methods to mitigate them are discussed. Finally, we extend the implications of our study to other photoinduced charging mechanisms prevalent in ion traps and discuss considerations in fabrication to reduce semiconductor charging.

关键词： Atomic & molecular processes in external fields Defects Photovoltaic effect Surface states Semiconductors Trapped ions Coherent control Finite-element method

Fermion-qubit fault-tolerant quantum computing

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arXiv 2024年

作者： Schuckert, Alexander Crane, Eleanor Gorshkov, Alexey V. Hafezi, Mohammad Gullans, Michael J. Joint Center for Quantum Information and Computer Science University of Maryland and NIST College ParkMD20742 United States Joint Quantum Institute University of Maryland and NIST College ParkMD20742 United States Departments of Physics and Mechanical Engineering Co-Design Center for Quantum Advantage Massachusetts Institute of Technology CambridgeMA02139 United States

Simulating the dynamics of electrons and other fermionic particles in quantum chemistry [1], material science [2], and high-energy physics [3] is one of the most promising applications of fault-tolerant quantum computers. However, the overhead in mapping time evolution under fermionic Hamiltonians to qubit gates [4–7] renders this endeavor challenging [8, 9]. We introduce fermion-qubit fault-tolerant quantum computing, a framework which removes this overhead altogether. Using native fermionic operations we first construct a repetition code which corrects phase errors only. We then engineer a fermionic color code which corrects for both phase and loss errors. We show how to realize a universal fermionic gate set in this code, including transversal Clifford gates. Interfacing with qubit color codes we realize qubit-fermion fault-tolerant computation, which allows for qubit-controlled fermionic time evolution, a crucial subroutine in state-of-the-art quantum algorithms for simulating fermions [10–13]. We show how our framework can be implemented in neutral atoms, overcoming the apparent inability of neutral atoms to implement non-number-conserving gates by introducing a neutral-atom braiding gate using photodissociation of bosonic molecules. As an application, we consider the fermionic fast Fourier transform, an important subroutine for simulating crystalline materials [12], finding an exponential improvement in circuit depth from O(N) to O(log(N)) with respect to lattice site number N and a linear improvement from O(N2) to O(N log(N)) in Clifford gate complexity compared to state-of-the-art qubit-only approaches [14]. Our work opens the door to fermion-qubit fault-tolerant quantum computation in platforms with native fermions such as neutral atoms, quantum dots and donors in silicon, with applications in quantum chemistry, material science, and high-energy physics. Copyright © 2024, The Authors. All rights reserved.

关键词： Nanocrystals

String-Breaking Dynamics in Quantum Adiabatic and Diabatic Processes

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arXiv 2024年

作者： Surace, Federica Maria Lerose, Alessio Katz, Or Bennewitz, Elizabeth R. Schuckert, Alexander Luo, De De, Arinjoy Ware, Brayden Morong, William Collins, Kate Monroe, Christopher Davoudi, Zohreh Gorshkov, Alexey V. Department of Physics Institute for Quantum Information and Matter California Institute of Technology PasadenaCA91125 United States Rudolf Peierls Centre for Theoretical Physics Clarendon Laboratory OxfordOX1 3PU United Kingdom Institute for Theoretical Physics KU Leuven Celestijnenlaan 200D Leuven3001 Belgium Duke Quantum Center Departments of Physics and Electrical and Computer Engineering Duke University DurhamNC27708 United States School of Applied and Engineering Physics Cornell University IthacaNY14853 United States Center for Quantum Information and Computer Science NIST University of Maryland College ParkMD20742 United States Joint Quantum Institute NIST University of Maryland College ParkMD20742 United States Department of Physics Maryland Center for Fundamental Physics University of Maryland College ParkMD20742 United States

Confinement prohibits isolation of color charges, e.g., quarks, in nature via a process called string breaking: the separation of two charges results in an increase in the energy of a color flux, visualized as a string, connecting those charges. Eventually, creating additional charges is energetically favored, hence breaking the string. Such a phenomenon can be probed in simpler models, including quantum spin chains, enabling enhanced understanding of string-breaking dynamics. A challenging task is to understand how string breaking occurs as time elapses, in an out-of-equilibrium setting. This work establishes the phenomenology of dynamical string breaking induced by a gradual increase of string tension over time. It, thus, goes beyond instantaneous quench processes and enables tracking the real-time evolution of strings in a more controlled setting. We focus on domain-wall confinement in a family of quantum Ising chains. Our results indicate that, for sufficiently short strings and slow evolution, string breaking can be described by the transition dynamics of a two-state quantum system akin to a Landau-Zener process. For longer strings, a more intricate spatiotemporal pattern emerges: the string breaks by forming a superposition of bubbles (domains of flipped spins of varying sizes), which involve highly excited states. We finally demonstrate that string breaking driven only by quantum fluctuations can be realized in the presence of sufficiently long-ranged interactions. This work holds immediate relevance for studying string breaking in quantum-simulation experiments. Copyright © 2024, The Authors. All rights reserved.

关键词： Excited states

Niobium doping induced mirror twin boundaries in MBE grown WSe2 monolayers

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Nano Research 2020年第7期13卷 1889-1896页

作者： Bo Wang Yipu Xia Junqiu Zhang Hannu-Pekka Komsa Maohai Xie Yong Peng Chuanhong Jin Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education School of Physical Science and TechnologyLanzhou UniversityLanzhou 730000China State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310024China Physics Department The University of Hong KongPokfulam RoadHong Kong 999077China Department of Applied Physics Aalto University00076 AaltoFinland Hunan Institute of Advanced Sensing and Information Technology Xiangtan UniversityXiangtan 411201China

Mirror twin boundary(MTB)brings unique one-dimensional(1D)physics and properties into two-dimensional(2D)transition metal dichalcogenides(TMDCs),but they were rarely observed in non-Mo-based ***,by post growth Nb doping,high density 4|4E-W and 4|4P-Se mirror twin boundaries(MTBs)were introduced into molecular beam epitaxy(MBE)grown WSe2 *** them,4|4E-W MTB with a novel structure was discovered experimentally for the first time,while 4|4P-Se MTBs present a random permutations of W and Nb,forming a 1D alloy *** between the doped and non-doped WSe2 confirmed that Nb dopants are essential for MTB ***,quantitative statistics reveal the areal density of MTBs is directly proportional to the concentration of Nb *** unravel the injection pathway of Nb dopants,first-principles calculations about a set of formation energies for excess Nb atoms with different configurations were conducted,based on which a model explaining the origin of MTBs introduced by excess metal was *** conclude that the formation of MTBs is mainly driven by the collective evolution of excess Nb atoms introduced into the lttice of host WSe2 crystal and subsequent displacement of metal atoms(W or Nb).This study provides a novel way to tailor the MTBs in 2D TMDC materials via proper metal doping and presents new opportunities for exploring the intriguing properties.

关键词： mirror twin boundaries niobium doping molecular beam epitaxy transition metal dichalcogenides niobium tungsten diselenide