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Momentum considerations inside near-zero index materials

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Light(Science & Applications) 2022年第8期11卷 1782-1789页

作者： Michaël Lobet Iñigo Liberal Larissa vertchenko andrei vlavrinenko Nader Engheta Eric Mazur John A.Paulson School of Engineering and Applied Sciences Harvard University9 Oxford StreetCambridgeMA02138USA Department of Physics and Namur Institute of Structured Materials University of NamurRue de Bruxelles 515000NamurBelgium Electrical and Electronic Engineering Department Universidad Pública de NavarraCampus ArrosadíaPamplona31006Spain Department of Photonics Engineering Technical University of DenmarkØrsteds Plads 345ADK-2800 KgsLyngbyDenmark Department of Electrical and Systems Engineering University of PennsylvaniaPhiladelphiaPA19104USA

Near-zero index (NZI) materials, i.e., materials having a phase refractive index close to zero, are known to enhance or inhibit light-matter interactions. Most theoretical derivations of fundamental radiative processes rely on energetic considerations and detailed balance equations, but not on momentum considerations. Because momentum exchange should also be incorporated into theoretical models, we investigate momentum inside the three categories of NZI materials, i.e., inside epsilon-and-mu-near-zero (EMNZ), epsilon-near-zero (ENZ) and mu-near-zero (MNZ) materials. In the context of Abraham–Minkowski debate in dispersive materials, we show that Minkowski-canonical momentum of light is zero inside all categories of NZI materials while Abraham-kinetic momentum of light is zero in ENZ and MNZ materials but nonzero inside EMNZ materials. We theoretically demonstrate that momentum recoil, transfer momentum from the field to the atom and Doppler shift are inhibited in NZI materials. Fundamental radiative processes inhibition is also explained due to those momentum considerations inside three-dimensional NZI materials. Absence of diffraction pattern in slits experiments is seen as a consequence of zero Minkowski momentum. Lastly, consequence on Heisenberg inequality, microscopy applications and on the canonical momentum as generator of translations are discussed. Those findings are appealing for a better understanding of fundamental light-matter interactions at the nanoscale as well as for lasing applications.

关键词： materials. momentum Minkowski

Giant photoinduced reflectivity modulation of nonlocal resonances in silicon metasurfaces

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Advanced Photonics 2023年第6期5卷 83-91页

作者： Andrea Tognazzi Paolo Franceschini Olga Sergaeva Luca Carletti Ivano Alessandri Giovanni Finco Osamu Takayama Radu Malureanu andrei v.lavrinenko Alfonso C.Cino Domenico de Ceglia Costantino De Angelis University of Palermo Department of EngineeringPalermoItaly National Institute of Optics-National Research Council PalermoItaly University of Brescia Department of Information EngineeringPalermoItaly ITMO University School of Physics and EngineeringSaint-PetersburgRussia ETH Zurich Institute for Quantum ElectronicsDepartment of PhysicsOptical Nanomaterial GroupZurichSwitzerland Technical University of Denmark Department of Electrical and Photonics EngineeringKongens LyngbyDenmark

Metasurfaces offer a unique playground to tailor the electromagnetic field at subwavelength scale to control polarization,wavefront,and nonlinear *** of the optical response of these structures is challenging due to the nanoscale size of their constitutive elements.A long-sought solution to achieve tunability at the nanoscale is all-optical modulation by exploiting the ultrafast nonlinear response of ***,the nonlinear response of materials is inherently very weak,and,therefore,requires optical excitations with large values of *** show that by properly tuning the equilibrium optical response of a nonlocal metasurface,it is possible to achieve sizable variation of the photoinduced out-ofequilibrium optical response on the picosecond timescale employing fluences smaller than 250μJ∕cm^(2),which is 1 order of magnitude lower than previous studies with comparable reflectivity variations in silicon *** results pave the way to fast devices with large modulation amplitude.

关键词： nonlocal metasurface nanophotonics ultrafast modulation Fano resonance

Silica-Metal Spherules in Ignimbrites of Southern Primorye,Russia

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Journal of Earth Science 2011年第1期22卷 20-31页

作者： andrei v Grebennikov Far East Geological Institute Prospect Stoletia 159 690022 Vladivostok Russia

A comprehensive mineralogical-geochemical and petrological study of ignimbrites from the Yakut-Gora volcanic depression （Primorye, Far Eastern Russia） revealed a wide distribution of silica-metal spherules （＂globules＂） that are typical liquid immiscibility resultant. The metallic portion of a spherule （composition varies from low-carbon iron to cohenite） borders gas pores and is rimmed by symplectite that consists of quartz, magnetite, and silica-potassic glass. This allows us to consider that the whole formation formed through reduction of the enclosing silicate melt. Abundant evidence of high reduction states of ignimbrite melts and the presence of iron carbides suggest an H2-CH4 composition of the fluidal phase in ignimbrite magmas.

关键词： spherule native iron ignimbrite tektite Primorye Russia.

Paleocene A-type igneous suites in the Sikhote-Alin(the East Asian continental margin):Petrological,geochronological,isotopic,and geodynamic constraints

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Geoscience Frontiers 2023年第6期14卷 386-413页

作者： andrei v.Grebennikov Sergei A.Kasatkin Far East Geological Institute Far Eastern Branch of the Russian Academy of Sciences159Prospekt 100-letiya VladivostokaVladivostok 690022Russian Federation

Global geodynamic reconstruction models of the Pacific margin of Asia refer to materials collected throughout Japan,Korea and northeastern China,but they lack data on southern ***,the Sikhote-Alin orogenic belt(NE Asia)constituted a single eastern margin of the paleo-Asian continent with the abovementioned territories in the *** isotopic,geochemical,and geochronological data show that Paleocene igneous activity(-61-55 Ma)is widely developed in south-ern *** rock compositions of the igneous rocks of this period yield ferroan,peraluminous,calc-alkaline to alkaline affinities,highly abundant LILE and HFSE(with pronounced Ba,Sr,Eu,and Ti neg-ative anomalies)and depleted *** initial melts,displaying Zr+Y+Ce+Nb>350 ppm and 10,000×Ga/Al>2.6,derived from an OIB-like mantle source crystallised under fairly reducing conditions(below FMQ buffer),and yield high temperature of zircon saturation(>850℃),indicating typical A-type granite and related volcanic rock *** is logical to associate variations in A-type rock geochemical composition with an enrichment of the upper part of the magma chamber with fluid-mobile components involving a reditribution of major and trace elements through fluid-magmatic *** depletion in Ca,Mg,Ba,Sr,Eu in the A-type rocks is caused by an outflow of these elements by an oxi-dizing,initially reduced,acidic fluid beyond the zone of magma ***-rock Sr-Nd isotope data argue for the generation of the A-type rocks by melting of dominantly a juvenile mantle component with a subordinate component of the ancient *** variations of igneous rocks of the reference area:^(87)Sr/^(86)Sr(t)(0.7024-0.7118),ε_(Nd)(t)(-0.9 to-5.1)and T_(DM2)(934-1277 Ma),result from the mixing of the OIB-like mantle source with selective melts or from the metapelite contamination of the Samarka terrane accretionary prism and of the Zhuravlevka-Amur turbidite basin,later followed by fluid-magma

关键词： Post-subduction magmatism Slab tear Sub-slab asthenosphere Strike-slip tectonic setting Lanthanide tetrad effect

Time-resolved terahertz spectroscopy of charge carrier dynamics in the chalcogenide glass As_(30)Se_(30)Te_(40)[Invited]

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Photonics Research 2016年第3期4卷 22-28页

作者： Tianwu Wang Elena A.Romanova Nabil Abdel-Moneim David Furniss Anna Loth Zhuoqi Tang Angela Seddon Trevor Benson andrei lavrinenko Peter Uhd Jepsen Department of Photonics Engineering (DTU Fotonik) Technical University of Denmark Saratov State University Department of Physics Faculty of Engineering University of Nottingham

Broadband(1.6–18 THz) terahertz time-domain spectroscopy(THz-TDS) and time-resolved terahertz spectroscopy(TRTS) were performed on a 54 μm thick chalcogenide glass(As_(30)Se_(30)Te_(40)) sample with a two-color laser-induced air plasma THz system in transmission and reflection modes, respectively. Two absorption bands at 2–3 and 5–8 THz were observed. TRTS reveals an ultrafast relaxation process of the photoinduced carrier response, well described by a rate equation model with a finite concentration of mid-bandgap trap states for self-trapped *** photoinduced conductivity can be well described by the Drude–Smith conductivity model with a carrier scattering time of 12–17 fs, and we observe significant carrier localization effects. A fast refractive index change was observed 100 fs before the conductivity reached its maximum, with 2 orders of magnitude larger amplitude than expected for the optically induced THz Kerr effect, indicating that free carriers are responsible for the transient index change.

关键词： Te Invited Se Time-resolved terahertz spectroscopy of charge carrier dynamics in the chalcogenide glass As

Paleocene–early Eocene post-subduction magmatism in Sikhote-Alin (Far East Russia): New constraints for the tectonic history of the Izanagi-Pacific ridge and the East Asian continental margin

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Geoscience Frontiers 2021年第4期12卷 71-85页

作者： andrei v.Grebennikov Igor v.Kemkin Alexander I.Khanchuk Far East Geological Institute Far Eastern BranchRussian Academy of Sciencespr.100-letiya Vladivostok 159Vladivostok 690022Russia Institute of Geology of Ore Deposits PetrographyMineralogy and Geochemistry(IGEM)Russian Academy of Sciences35 Staromonetny Per.Moscow 109017Russia

New isotopic,geochemical and geochronological data justify the widespread occurrence of middle Paleocene to early Eocene(60–53 Ma)post-subduction felsic magmatism across the entire Sikhote-Alin territory(southeastern Russia),conform with previous observations in Northeast China,the southern Korean Peninsula,and the Inner Zone of *** igneous activity in East Asia coincided with the reactivation(after tectonic quiescence between~93–60Ma)of left-lateral strike-slip displacements along the Tan-Lu and Central Sikhote-Alin faults and with the post-60 Ma cessation of subduction/accretion recorded in the Shimanto belt of SW *** Sikhote-Alin post-subduction igneous A-type rocks present diverse mineralogical and geochemical features that suggest interactions of the subducting plate with anhydrous mantle upwelling through slab tears in the continental *** middle Paleocene–early Eocene magmatismis not related to subduction but is synchronous with strikeslip tectonics and the termination of accretionary prism development,suggesting a shift in tectonic regime from oceanic plate subduction at a convergent margin to parallel sliding and initiation of a transformcontinental *** new observations are inconsistent with the current tectonic model of 60–50 Ma Izanagi-Pacific ridge subduction beneath East Asian continental margin.

关键词： Post-subduction magmatism Slab tear Sikhote-Alin Paleocene A-type rocks Izanagi-Pacific ridge

Deep Forest as a framework for a new class of machine-learning models

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National Science Review 2019年第2期6卷 186-187页

作者： Lev v.Utkin Anna A.Meldo andrei v.Konstantinov Laboratory of Neural Network Technology and Artificial Intelligence Peter the Great St. Petersburg Polytechnic University

A new deep learning framework—the socalled Deep Forest (DF), proposed by Zhi-Hua Zhou and Ji Feng [1,2]—can be regarded as one of the important events of 2017 in machine learning, although it was unjustly unnoticed by a large number of researchers. The DF combines several ensemble-based methods, including Random Forests (RFs) and Stacking, into a structure that is similar to a multi-layer neural network, but each layer in the DF

关键词： Deep Forest as a framework for a new class of machine-learning models

Photoswitchable molecular dipole antennas with tailored coherent coupling in glassy composite

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Light(Science & Applications) 2015年第1期4卷 259-266页

作者： Mady Elbahri Ahnaf Usman Zillohu Bastian Gothe Mehdi Keshavarz Hedayati Ramzy Abdelaziz Hala Jarallah El-Khozondar Muhammad Bawa’aneh Moheb Abdelaziz andrei lavrinenko Sergei Zhukovsky Shahin Homaeigohar Nanochemistry and Nanoengineering Faculty of EngineeringInstitute for Materials ScienceUniversity of KielKaiserstrasse 224143 KielGermany Nanochemistry and Nanoengineering Institute of Polymer ResearchHelmholtz-Zentrum GeesthachtMax-Planck-Strasse 121502 GeesthachtGermany Refractories Ceramics and Building Materials DepartmentNational Research CentreDokkiCairoEgypt Electrical Engineering Department Islamic University of GazaGazaPO Box 108Palestine The Hashemite University Department of PhysicsZarqaJordan&Khalifa University of ScienceTechnology&Research(KUSTAR)PO Box 573SharjahUAE DTU Fotonik Technical University of DenmarkOersteds pl.343Kongens LyngbyDK-2800Denmark

Here,we introduce the first experimental proof of coherent oscillation and coupling of photoswitchable molecules embedded randomly in a polymeric matrix and acting cooperatively upon illumination with Uv *** particular,we demonstrate the specular reflection and Brewster phenomenon alteration of photochromic molecular dipole *** successfully demonstrate the concept of Brewster wavelength,which is based on the dipolar interaction between radiating dipoles and the surrounding matrix possessing a net dipole moment,as a key tool for highly localized sensing of matrix *** also introduce the concept of‘tailored molecular photonic coupling’while highlighting the role of interferences for the design of optically active media by adjusting the photonic response of the medium with the real and imaginary refractive index of photoswitchable molecules in the‘ON’*** results enhance our fundamental understanding of coherent dipole radiation and open a new vein of research based on glassy disordered dipolar composites that act as macroscopic antenna with cooperative action;furthermore,these results have important implications for new design rules of tailored photonics.

关键词： Brewster angle coherent coupling collective oscillation photoswitchable molecular photonics specular reflection

Hybrid Triboelectric-Electromagnetic Nanogenerators for Mechanical Energy Harvesting:A Review

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Nano-Micro Letters 2021年第12期13卷 163-220页

作者： Joao v.vidal vladislav Slabov andrei L.Kholkin Marco P.Soares dos Santos Department of Physics and CICECO-Aveiro Institute of Materials University of Aveiro3810-193 AveiroPortugal Department of Physics and I3N University of Aveiro3810-193 AveiroPortugal Laboratory of Functional Low-Dimensional Structures National University of Science and Technology MISISMoscowRussia Department of Mechanical Engineering Centre for Mechanical Technology and Automation(TEMA)University of Aveiro3810-193 AveiroPortugal

Motion-driven electromagnetictriboelectric energy generators(E-TENGs) hold a Hybrid triboelectric-electromagnetic generators C A Bgreat potential to provide higher voltages,higher currents and wider operating bandwidths than Cantilever generators1 μm both electromagnetic and triboelectric generators Rotating generatorsSliding generators standing alone. Therefore,they are promising solutions to autonomously supply a broad range of Flexible blade generators Magnetoelectric highly sophisticated devices. This paper provides generators a thorough review focused on major recent breakLinear generators Multidimensional generators throughs in the area of electromagnetic-triboelectric vibrational energy harvesting. A detailed Pendulum generators analysis was conducted on various architectures including rotational,pendulum,linear,sliding,cantilever,flexible blade,multidimensional and 1 cm magnetoelectric,and the following hybrid technologies. They enable highly e cient ways to harvest electric energy from many forms of vibrational,rotational,biomechanical,wave,wind and thermal sources,among others. Open-circuit voltages up to 75 v,short-circuit currents up to 60 mA and instantaneous power up to 144 mW were already achieved by these nanogenerators. Their transduction mechanisms,including proposed models to make intelligible the involved physical phenomena,are also overviewed here. A comprehensive analysis was performed to compare their respective construction designs,external excitations and electric outputs. The results highlight the potential of hybrid E-TENGs to convert unused mechanical motion into electric energy for both large-and small-scale ***,this paper proposes future research directions toward optimization of energy conversion e ciency,power management,durability and stability,packaging,energy storage,operation input,research of transduction mechanisms,quantitative standardization,system integration,miniaturization and multi-energy hybrid cells.

关键词： E-TENG Hybrid triboelectric-electromagnetic Nanogenerators Energy harvesting