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arXiv 2025年

作者： Damski, Bogdan Jagiellonian University Faculty of Physics Astronomy and Applied Computer Science Lojasiewicza 11 Kraków30-348 Poland

Long-range field configurations exist in the Proca theory and their non-equilibrium evolution is of interest in this work. General arguments suggest that a charge can be assigned to them and that its evolution is governed by the law of periodic charge oscillations. We discuss an elegant analytically-solvable example of a field configuration in the Proca theory respecting such a law. We also identify a weak point in the aforementioned general arguments, construct the counterexample to the law of periodic charge oscillations in the Proca theory, and comprehensively discuss it. The Gibbs-Wilbraham phenomenon is discussed in the course of these studies. Copyright © 2025, The Authors. All rights reserved.

关键词： Dynamics

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On-Chip Multidimensional Dynamic Control of Twisted Moiré Photonic Crystal for Smart Sensing and Imaging

arXiv

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arXiv 2023年

作者： Tang, Haoning Lou, Beicheng Du, Fan Gao, Guangqi Zhang, Mingjie Ni, Xueqi Hu, Evelyn Yacoby, Amir Cao, Yuan Fan, Shanhui Mazur, Eric School of Engineering and Applied Sciences Harvard University CambridgeMA02138 United States Department of Applied Physics Ginzton Laboratory Stanford University StanfordCA94305 United States Department of Physics Faculty of Art and Sciences Harvard University CambridgeMA02138 United States Department of Electrical Engineering and Computer Science University of California at Berkeley BerkeleyCA94720 United States

Reconfigurable optics, optical systems that have a dynamically tunable configuration, are emerging as a new frontier in photonics research. Recently, twisted moiré photonic crystal has become a competitive candidate for implementing reconfigurable optics because of its high degree of tunability. However, despite its great potential as versatile optics components, simultaneous and dynamic modulation of multiple degrees of freedom in twisted moiré photonic crystal has remained out of reach, severely limiting its area of application. In this paper, we present a MEMS-integrated twisted moiré photonic crystal sensor that offers precise control over the interlayer gap and twist angle between two photonic crystal layers, and demonstrate an active twisted moiré photonic crystal-based optical sensor that can simultaneously resolve wavelength and polarization. Leveraging twist- and gap-tuned resonance modes, we achieve high-accuracy spectropolarimetric reconstruction of light using an adaptive sensing algorithm, over a broad operational bandwidth in the telecom range and full Poincaré sphere. Our research showcases the remarkable capabilities of multidimensional control over emergent degrees of freedom in reconfigurable nanophotonics platforms and establishes a scalable pathway towards creating comprehensive flat-optics devices suitable for versatile light manipulation and information processing tasks. Extracting phase, polarization, and wavelength information from an optical signal typically necessitates the use of separate optical components, such as interferometers, polarizers, and narrow-band filters or spectrometers, that cannot easily be integrated1 and are limited in resolution and speed. Recently, however, computational sensing has made it possible to reconstruct target parameters from the optical signal obtained with a single © 2023, CC BY.

关键词： Photonic crystals

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Raman Signatures of Single Point Defects in Hexagonal Boron Nitride Quantum Emitters

arXiv

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arXiv 2025年

作者： Cholsuk, Chanaprom Çakan, Aslı Deckert, Volker Suwanna, Sujin Vogl, Tobias Department of Computer Engineering TUM School of Computation Information and Technology Technical University of Munich Munich80333 Germany Munich80799 Germany Institute of Physical Chemistry Friedrich-Schiller University Jena07743 Germany Leibniz Institute of Photonic Technology Jena07745 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

Point defects in solid-state quantum systems are vital for enabling single-photon emission at specific wavelengths, making their precise identification essential for advancing applications in quantum technologies. However, pinpointing the microscopic origins of these defects remains a challenge. In this work, we propose Raman spectroscopy as a robust strategy for defect identification. Using density functional theory, we systematically characterize the Raman signatures of 100 defects in hexagonal boron nitride (hBN) spanning periodic groups III to VI, encompassing around 30,000 phonon modes. Our findings reveal that the local atomic environment plays a pivotal role in shaping the Raman lineshape, enabling the narrowing of potential defect candidates. Furthermore, we demonstrate that Raman spectroscopy can differentiate defects based on their spin and charge states as well as strain-induced variations, implying the versatility of this approach. Therefore, this study not only provides a comprehensive theoretical database of Raman spectra for hBN defects but also establishes a novel experiment framework for using tip-enhanced Raman spectroscopy to identify point defects. More broadly, our approach offers a universal method for defect identification in any quantum materials. Copyright © 2025, The Authors. All rights reserved.

关键词： Point defects

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Sawtooth lattice multiferroic BeCr2O4: Noncollinear magnetic structure and multiple magnetic transitions

引用

Physical Review Materials 2023年第2期7卷 024422-024422页

作者： Hector Cein Mandujano Alejandro Metta Neven Barišić Qiang Zhang Wojciech Tabiś Naveen Kumar Chogondahalli Muniraju Harikrishnan S. Nair Department of Physics 500 West University Avenue University of Texas at El Paso El Paso Texas 79968 USA Department of Chemistry 500 West University Avenue University of Texas at El Paso El Paso Texas 79968 USA Institute of Solid State Physics Vienna University of Technology Wiedner Hauptstrße 8–10 1040 Vienna Austria Department of Physics Faculty of Science University of Zagreb Bijenička cesta 32 10000 Zagreb Croatia Neutron Scattering Division Oak Ridge National Laboratory Oak Ridge Tennessee 37830 USA AGH University of Science and Technology Faculty of Physics and Applied Computer Science 30-059 Krakow Poland The Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences 152 Radzikowskiego Strasse 31-342 Krakow Poland Institute of Physics Bijenička cesta 46 HR-10000 Zagreb Croatia

Noncollinear magnetic structures and multiple magnetic phase transitions in a sawtooth lattice antiferromagnet consisting of Cr3+ are experimentally identified in this work, thereby proposing the scenario of magnetism-driven ferroelectricity in a sawtooth lattice. The title compound, BeCr2O4, displays three magnetic phase transitions at low temperatures—at TN1≈7.5 K, at TN2≈25 K, and at TN3≈26 K—revealed through magnetic susceptibility, specific heat, and neutron diffraction in this work. These magnetic phase transitions are found to be influenced by externally applied magnetic fields. Isothermal magnetization curves at low temperatures below the magnetic transitions indicate the antiferromagnetic nature of BeCr2O4 with two spin-flop-like transitions occurring at Hc1≈29 kOe and Hc2≈47 kOe. Our high-resolution x-ray and neutron diffraction studies, performed on single crystal and powder samples, unambiguously determined the crystal structure as orthorhombic Pbnm. By performing the magnetic superspace group analysis of the neutron diffraction data at low temperatures, the magnetic structure in the temperature range TN3,N2

关键词： Multiferroics Neutron diffraction X-ray diffraction

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On the probabilistic quantum error correction

arXiv

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arXiv 2022年

作者： Kukulski, Ryszard Pawela, Lukasz Puchala, Zbigniew Institute of Theoretical and Applied Informatics Polish Academy of Sciences Baltycka 5 Gliwice44-100 Poland Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University ul. Lojasiewicza 11 Kraków30-348 Poland

Probabilistic quantum error correction is an error-correcting procedure which uses postselection to determine if the encoded information was successfully restored. In this work, we deeply analyze probabilistic version of the error-correcting procedure for general noise. We generalized the Knill-Laflamme conditions for probabilistically correctable errors. We show that for some noise channels, we should encode the information into a mixed state to maximize the probability of successful error correction. Finally, we investigate an advantage of the probabilistic error-correcting procedure over the deterministic one. Reducing the probability of successful error correction allows for correcting errors generated by a broader class of noise channels. Significantly, if the errors are caused by a unitary interaction with an auxiliary qubit system, we can probabilistically restore a qubit state by using only one additional physical qubit. © 2022, CC BY.

关键词： Error correction

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Multi-Agent Economic Modeling Automation Technologies 9

Multi-Agent Economic Modeling Automation Technologies

引用

9th International Conference on Control, Decision and Information Technologies, CoDIT 2023

作者： Zhukova, Aleksandra A. Pilnik, Nikolai P. Kamenev, Ivan G. Iusup-Akhunov, Batyrzhan B. Federal Research Center 'Computer Science and Control' of the Russian Academy of Sciences Department of Mathematical Modelling in Economic Social and Ecological Systems Vavilov st. 44 building 2 Moscow119333 Russia Federal Research Center 'Computer Science and Control' of the Russian Academy of Sciences Department of Mathematical Modelling of Economic Systems Vavilov st. 44 building 2 Moscow119333 Russia Hse University Faculty of Economic Sciences Department of Applied Economics Pokrovsky Bulvar 11 Moscow109028 Russia Fsbeihe Bauman Moscow State Technical University Department of Fundamental Sciences-11 2nd Baumanskaya street 5-1 Moscow05005 Russia The Phystech School of Applied Mathematics and Informatics Moscow Institute of Physics and Technology 9 Institutskiy per. Moscow Region Dolgoprudny141701 Russia

ISBN: (纸本)9798350311402

Complex economic models often describe the agent's decisions, i.e. choice of some controlled variables in accordance with criteria set by agents. Unlike purely statistical ones, agent-based models allow to describe processes with different modes, in which the agent's behavior changes quali-tatively when the environment (including the actions of other agents) change. The practical use of mathematical models of complex systems with a number of interacting agents is limited by complexity of their construction and possible errors when dealing with multitude of expressions. computer tools, such as the 'Ecomod' system discussed in the article, can substantially reduce the time spent on model creation and processing, and help to coordinate the work of several researchers on the model. © 2023 IEEE.

关键词： Autonomous agents

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Water and Moganite Distribution in Agates from Bou Hamza, Morocco: Constraints from a Combined Microscopic and Spectroscopic Study

SSRN

引用

SSRN 2024年

作者： Powolny, Tomasz Dumańska-Slowik, Magdalena Szczerbowska-Boruchowska, Magdalena Woszczyna, Maciej University of Silesia in Katowice Faculty of Natural Sciences Institute of Earth Sciences 60 Będzińska St. Sosnowiec41-200 Poland AGH University of Kracow Faculty of Geology Geophysics and Environmental Protection 30 Mickiewicza Ave. Kraków30-059 Poland AGH University of Kracow Faculty of Physics and Applied Computer Science 19 Reymonta St. Kraków30-059 Poland

The monocentric agates from Bou Hamza (Morocco), hosted by Triassic basaltic rocks, are mainly composed of length-fast (LF) chalcedony, involving non-twisted (,,normal") and wall-lining twisted (,,zebraic") one. The ,,zebraic" type is further interbedded with minor length-slow (LS) chalcedony (quartzine). Apart from chalcedonic silica, the agates host recrystallization-related quartz microtextures, i.e. feathery and mosaic (jigsaw-puzzle), as well as prismatic elongated megaquartz. The following study shows the relationship between these forms of SiO2, and moganite and water contents estimated using Raman spectroscopy and Fourier-transformed infrared spectroscopy, respectively. Moganite reaches up to ca. 21 and 31 wt.% in LF ,,normal" and LF ,,zebraic" chalcedony, but only up to ca. 18 wt.% in LS chalcedony. These variations were likely facilitated by the physicochemical fluctuations of circulating fluids (alkalinity and Fe content), self-organization of silica, and/or variable rates of recrystallization. The latter mechanism has also resulted in the fibrosity to granularity transformation developed in LF ,,zebraic" chalcedony, which should be thus considered asa ,,metastable" variety of silica. Feathery and mosaic quartz show low and high moganite contest (i.e. 0 and up to 34 wt.%, respectively) owing to their formation from different precursors (e.g. opaline-rich moganite-poor and chalcedonic moganite-rich, respectively), whilst prismatic megaquartz is impoverished in moganite admixture. The content of total water ranges from ca. 0.4 wt.% in megaquartz to ca. 0.4-0.5 wt.% in chalcedonic silica, and up to 0.6 wt.% in feathery quartz. It mostly embraces molecular water with variable addition of hydrogen-bonded silanol-group water. Meanwhile, these water species appear to compensate each other to produce a relatively stable total water content across chalcedonic bands, as predicted by a condensation reaction of silanols (Si–OH) in a closed system. The formation of th

关键词： Recrystallization (metallurgy)

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Design of Miniaturized Metamaterial Reflector with Doubly Interdigital Structure for 5G Use Cases

Design of Miniaturized Metamaterial Reflector with Doubly In...

引用

13th International Electrical Engineering Congress, iEECON 2025

作者： Somwong, Tanee Chomtong, Pongsathorn Khamsuthat, Jirayut Chudpooti, Nonchanutt Akkaraekthalin, Prayoot Rajamangala University of Technology Suvarnabhumi Faculty of Engineering and Architecture Department of Electronic and Telecommunications Engineering Nonthaburi Thailand King Mongkut's University of Technology North Bangkok Faculty of Technical Education Department of Teacher Training in Electrical Engineering Bangkok Thailand King Mongkut's University of Technology North Bangkok Faculty of Applied Science Department of Industrial Physics and Medical Instrumentation Bangkok Thailand King Mongkut's University of Technology North Bangkok Faculty of Engineering Department of Electrical and Computer Engineering Bangkok Thailand

ISBN: (纸本)9798331543952

This paper presents the design of a miniaturized metamaterial reflector composing of an open-loop transmission line unit cell structure. The transmission line ends are connected by using a double interdigital technique, resulting in a large capacitive value compared to the conventional methods. When combined with the open-loop line employing the trisection step-impedance structure with adjusting of the capacitive value, its second and third resonant frequencies will be controllable. As a result, this approach can reduce the unit cell size from a typical value of λ/2 to an approximate value of λ/16, therefore overall size of the reflector is significantly decreased. The designed unit cell is measured to be 1.05 cm × 1.0 cm. We implemented the proposed reflector on an FR-4 PCB with a relative permittivity of about 4.4, a substrate height (h) of 1.6 mm, and a loss tangent of about 0.02. The operating frequency range targets of 5G use cases were set to be at 1.8 GHz, 2.6 GHz and 3.5 GHz, respectively. When used with a dipole antenna, the bandwidths of 390 MHz, 604 MHz, and 1.1 GHz and the antenna gains of about 8.23 dB, 8.14 dB, and 8.19 dB were obtained at the operating frequencies, respectively. © 2025 IEEE.

关键词： Antenna reflectors

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Design of Miniaturized Metamaterial Reflector with Doubly Interdigital Structure for 5G Use Cases

Design of Miniaturized Metamaterial Reflector with Doubly In...

引用

International Electrical Engineering Congress (iEECON)

作者： Tanee Somwong Pongsathorn Chomtong Jirayut Khamsuthat Nonchanutt Chudpooti Prayoot Akkaraekthalin Department of Electronic and Telecommunications Engineering Faculty of Engineering and Architecture Rajamangala University of Technology Suvarnabhumi Nonthaburi Thailand Department of Teacher Training in Electrical Engineering Faculty of Technical Education King Mongkut’s University of Technology North Bangkok Bangkok Thailand Department of Industrial Physics and Medical Instrumentation Faculty of Applied Science King Mongkut’s University of Technology North Bangkok Bangkok Thailand Department of Electrical and Computer Engineering Faculty of Engineering King Mongkut’s University of Technology North Bangkok Bangkok Thailand

ISBN: (数字)9798331543952

ISBN: (纸本)9798331543969

关键词： Wireless communication 5G mobile communication Dipole antennas Simulation Resonant frequency Reflector antennas Transmission line measurements Metamaterials Gain Substrates

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Optimization of Carbon Dot Deposition on Polycarbonate Substrates Via Non-Thermal Plasma: Exploring its Superhydrophobic Properties and Ph Sensing Capabilities

SSRN

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SSRN 2024年

作者： Selvaraj, Yuvaraj Venkatraman, M.R. Govindaraj, Rajesh Carrasco, Marcos Flores Natarajan, Muthukumarasamy Velauthapillai, Dhayalan Devaraj, Kamalraj Yoganand, Cp. Jaffer, Syed S. Department of Physics Coimbatore Institute of Technology Coimbatore641014 India Department of Physics Sri Shakthi Institute of Engineering and Technology Coimbatore641062 India Centre for Computational Modelling Chennai Institute of Technology Chennai600069 India Centre for Research in Pure and Applied Sciences JAIN [Deemed-to-be-University Bengaluru560069 India Department of Physics Faculty of Physical and Mathematical Sciences University of Chile Santiago265 Chile Department of Computer Science Electrical Engineering and Mathematical Sciences Western Norway University of Applied Science Bergen5063 Norway Department of Chemistry Coimbatore Institute of Technology Coimbatore641014 India

Carbon dots (CDs) are a class of highly photoluminescent nanomaterials that are less toxic, exhibit good compatibility in biological studies, and they are of sizes typically below 10 nm. In the present work, CDs were implanted on the surface of polycarbonate (PC) using the DC glow discharge non-thermal plasma technique. Plasma processing is a versatile technique to produce nanomaterials that can be used for biomedical and sensor applications. Monitoring the input voltage, processing time, and gas flow-rate are the crucial parameters that play a major role in optimal processing to impregnate CDs on PC. Acetylene plasma processed PC was subjected to an acid isolation process for accumulation of CDs and to test its usage in pH sensing and optical applications. Structural and graphitic layer formation of CDs on PC was studied through Raman spectroscopy, amorphous nature of the samples were observed from the XRD results. The uniform distribution of carbons over the PC was witnessed from the FESEM images and the isolated CDs were identified through and TEM microscopic images. The pH-sensitive photoemission property of acid isolated CDs was analyzed using fluorescence spectrophotometer and the observed results from 3D-contour fluorescent spectra revealed that the KMnO4 treated CDs showed interesting behaviour that can be used in biological pH sensors. The superhydrophobic nature of the prepared samples were observed through the contact angles measurements for water and blood respectively. Contact angle results suggest that the plasma processed CDs can be used in applications involving blood contact devices. © 2024, The Authors. All rights reserved.

关键词： pH sensors

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