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Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas F.Sadreev Yong Li andrey e.Miroshnichenko School of Physics and electronic Sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical engineering Rowan University School of engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Control of light scattering by nanoparticles with optically-induced magnetic responses

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Chinese Physics B 2014年第4期23卷 41-51页

作者：刘伟 andrey e. Miroshnichenko Yuri S. Kivshar College of Optoelectronic Science and engineering National University of Defence Technology Nonlinear Physics Center and Center for Ultrahigh-bandwidth Devices for Optical Systems CUDOS) Research School of Physics and EngineeringAustralian National University

Conventional approaches to control and shape the scattering pattems of light generated by different nanostructures are mostly based on engineering of their electric response due to the fact that most metallic nanostructures support only electric resonances in the optical frequency range. Recently, fuelled by the fast development in the fields of metamaterials and plasmonics, artificial optically-induced magnetic responses have been demonstrated for various nanostructures. This kind of response can be employed to provide an extra degree of freedom for the efficient control and shaping of the scattering patterns of nanoparticles and nanoantennas. Here we review the recent progress in this research direction of nanoparticle scattering shaping and control through the interference of both electric and optically-induced magnetic responses. We discuss the magnetic resonances supported by various structures in different spectral regimes, and then summarize the original results on the scattering shaping involving both electric and magnetic responses, based on the interference of both spectrally separated （with different resonant wavelengths） and overlapped dipoles （with the same resonant wavelength）, and also other higher-order modes. Finally, we discuss the scattering control utilizing Fano resonances associated with the magnetic responses.

关键词： optically-induced magnetic response scattering control Mie resonance Fano resonance

Loess deposition in Asia： its initiation and development before and during the Quaternary

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episodes 2008年第2期31卷 222-225页

作者： andrey e. Dodonov Liping Zhou Geological Institute Russian Academy of Sciences Pyzhevsky 7 119017 Moscow Russia Laboratory for earth Surface Processes Department of Geography Peking University Beijing 100871 China

Dust is important in the earth environment system. However; the role of dust in climate change remains largely unknown. A better understanding of the temporal and spatial variability of the dust accumulation in Asia forms an important step towards establishing the link between dust deposition and climate change. Here, a summary is given for the timing of the onset and expansion of loess deposition in Asia beginning in the early, Miocene. Recent progress on some aspects of loess chronology and palaeoenvironmental reconstruction is also reviewed.

关键词：亚洲黄土沉积第四纪地质时代地球环境

Juvenile survival curves in a solitary ground squirrel with a prolonged hibernation:effects of individual characteristics,environment,and maternal investment

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Current Zoology 2024年第1期70卷 13-23页

作者： Nina A.Vasilieva Liudmila e Savinetskaya andrey V.Tchabovsky A.N.Severtsov Institute of ecology and evolution Russian Academy of SciencesMoscow 119071Russia

Juvenile survival is a key life-history influence on population dynamics and adaptive *** analyzed the effects of individual chara-cteristics,early environment,and maternal investment on juvenile survival in a large solitary hibernating rodent-yellow ground squirrel Spermophilus fulvus using Cox mixed-effects *** 48%of weaned pups survived to dispersal and 17%survived to *** life expectancy was primarily determined by individual characteristics and,to a lesser extent,by the early *** strongest and pos-itive predictor of juvenile survival was body mass which crucially affected mortality immediately after *** suffered higher mortality than females after the onset of dispersal;however,the overall difference between sexes was partly masked by high rates of mortality in the first days after emergence in both *** emerged juveniles had lower life expectancy than the earliest *** overall effect of local juvenile density was *** lactation did not enhance juvenile survival:Pups nursed longer survived shorter than the young nursed for a shorter *** findings support the hypothesis that females of *** cannot effectively regulate maternal expenditures to mitigate the effects of unfavorable conditions on their *** strategy to deal with seasonal time constraints on life history in female *** suggests an early termination of maternal care at the cost of juvenile quality and *** female reproductive strategy corresponds to a"fast-solitary"life of folivorous desert-dwelling *** and other solitary ground squirrels with prolonged hibernation.

关键词： early-life conditions ground squirrels hibernation juvenile mortality maternal investment survival curves

Influence of frost weathering on the recession of surfaces of technogenic landforms in Yakutia

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Research in Cold and Arid Regions 2019年第4期11卷 257-266页

作者： andrey e.Melnikov Nikolay N.Grib Melnikov Permafrost Institute of the Siberian Branch of the Russian Academy of Sciences Yakutsk 677010Russia Technical Institute(branch)of M.K.Ammosov North-eastern Federal University Neryungri 678960Russia

The article assesses the influence of permafrost weathering on the rate of destruction of technogenic land forms,as exhibit ed on as illustrated by the railway embankment of the Amur Yakut mainline in the Sakha Republic(Yakutia).Studies were carried out on a railway section more than 375 km *** subsidence rate of the embankment slopes and structur al excavations was determined using laboratory methods that simulate various mechanisms of temperature(with a transi tion through 0℃)impact on *** the first time,a quantitative assessment of the influence of cryogenic weathering on the stability of the railway in the region belonging to the northern building climatic zone is *** the territory un der consideration,embankment rocks were experimentally determined to undergo more than 100 freezing and thawing cy cles during a *** the existing climatic conditions,cryogenic weathering actively affects the embankment of the railway to a depth of 30 *** of the embankment deformations detected during field observations are due to defects in the integrity of this particular *** size of the disintegrating layer of particular types of rock comprising the rail way embankment has been established as reaching 10 cm per *** 5 years following the formation of embankments comprising the upper structure of the railroad tracks,the physical and mechanical properties of rocks,which initially had a tensile strength for uniaxial compression in the range of 40 70 MPa,were reduced by more than 50%.According to the authors,the establishment of regional cryohypergenesis features is universal in nature and can be applied to solving a wide range of tasks related to the assessment and prediction of the degree of cryogenic transformation of rocks having different structural properties.

关键词： cryogenic weathering embankment railway subsidence rate Republic of Sakha Yakutia

Strong coupling and catenary field enhancement in the hybrid plasmonic metamaterial cavity and TMDC monolayers

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Opto-electronic Advances 2024年第5期7卷 20-32页

作者： Andergachew Mekonnen Berhe Khalil As’ham Ibrahim Al-Ani Haroldo T.Hattori andrey e.Miroshnichenko School of engineering and Technology University of New South Wales at CanberraNorthcott DriveCanberra ACT 2610Australia

Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy *** plasmon-exciton strong coupling,plasmonic nanocavities play a significant role due to their ability to confine light in an ultrasmall ***,two-dimensional transition metal dichalcogenides(TMDCs) have a significant exciton binding energy and remain stable at ambient conditions,making them an excellent alternative for investigating light-matter *** a result,strong plasmon-exciton coupling has been reported by introducing a single metallic ***,single nanoparticles have lower spatial confinement of electromagnetic fields and limited tunability to match the excitonic ***,we introduce the concept of catenary-shaped optical fields induced by plasmonic metamaterial cavities to scale the strength of plasmon-exciton *** demonstrated plasmon modes of metallic metamaterial cavities offer high confinement and tunability and can match with the excitons of TMDCs to exhibit a strong coupling regime by tuning either the size of the cavity gap or *** calculated Rabi splitting of Au-MoSe_2 and Au-WSe_2 heterostructures strongly depends on the catenary-like field enhancement induced by the Au cavity,resulting in room-temperature Rabi splitting ranging between 77.86 and 320 me *** plasmonic metamaterial cavities can pave the way for manipulating excitons in TMDCs and operating active nanophotonic devices at ambient temperature.

关键词： catenary-shaped field enhancement strong coupling plasmon exciton Rabi splitting

Neuromorphic nanocluster networks:Critical role of the substrate in nano-link formation

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Nano Research 2023年第7期16卷 10500-10506页

作者： Wenkai Wu Alexey V.Verkhovtsev Theodoros Pavloudis andrey V.Solov’yov Richard e.Palmer Nanomaterials Lab Faculty of Science and EngineeringSwansea UniversityBay CampusFabian WaySA18ENSwanseaUK MBN Research Center Altenhöferallee 360438 Frankfurt am MainGermany School of Physics Faculty of SciencesAristotle University of ThessalonikiGR-54124 ThessalonikiGreece

Atomic cluster-based networks represent a promising architecture for the realization of neuromorphic computing systems,which may overcome some of the limitations of the current computing *** formation and breakage of links between the clusters are of utmost importance for the functioning of these computing *** paper reports the results of molecular dynamics simulations of synapse(bridge)formation at elevated temperature and thermal breaking processes between 2.8 nmsized Au1415 clusters deposited on a carbon substrate,a model ***,we find that the bridge formation process is driven by the diffusion of gold atoms along the substrate,no matter how small the gap between the clusters *** complementary simulations of the bridge breaking process reveal the existence of a threshold bias voltage to activate bridge rupture via Joule *** results provide an atomistic-level understanding of the fundamental dynamical processes occurring in neuromorphic cluster arrays.

关键词： atomic-switch network nanoclusters nanoparticles(NPs) clusters on surfaces synapse neuromorphics molecular dynamics(MD)

Supercurrent decay in ballistic magnetic Josephson junctions

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npj Computational Materials 2022年第1期8卷 186-196页

作者： HervéNess Ivan A.Sadovskyy andrey e.Antipov Mark van Schilfgaarde Roman M.Lutchyn Department of Physics King’s College LondonStrand CampusLondonWC2R 2LSUK Microsoft Quantum Microsoft Station QUniversity of CaliforniaSanta BarbaraCA93106USA National Renewable energy Laboratory GoldenCO80401USA

We investigate transport properties of ballistic magnetic Josephson junctions and establish that suppression of supercurrent is an intrinsic property of the junctions,even in absence of *** studying the role of ferromagnet thickness,magnetization,and crystal orientation we show how the supercurrent decays exponentially with thickness and identify two mechanisms responsible for the effect:(i)large exchange splitting may gap out minority or majority carriers leading to the suppression of Andreev reflection in the junction,(ii)loss of synchronization between different modes due to the significant dispersion of the quasiparticle velocity with the transverse *** results for Nb/Ni/Nb junctions are in good agreement with recent experimental *** approach combines density functional theory and the Bogoliubov-de Gennes model and opens a path for material composition optimization in magnetic Josephson junctions and superconducting magnetic spin valves.

关键词： Josephson decay magnetic

Charged pion condensation in anti-parallel electromagnetic fields and nonzero isospin density

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Chinese Physics C 2020年第3期44卷 101-110页

作者： Jingyi Chao Mei Huang andrey Radzhabov Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Matrosov Institute for System Dynamics and Control Theory SB RAS Lermontov str. 134664033IrkutskRussia

The formation of charged pion condensate in anti-parallel electromagnetic fields and in the presence of the isospin chemical potential is studied in the two-flavor Nambu-Jona-Lasinio *** method of Schwinger proper time is extended to explore the quantities in the off-diagonal flavor space,*** charged *** this framework,π^± are treated as bound states of quarks and not as point-like charged *** isospin chemical potential plays the role of a trigger for charged pion *** obtain the associated effective potential as a function of the strength of the electromagnetic fields and find that it contains a sextic term which possibly induces a weak first order phase *** dependence of pion condensation on model parameters is investigated.

关键词： pion condensate electromagnetic fields weakly first order phase transition