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A bridge for accelerating materials by design

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npj Computational Materials 2015年第1期1卷 56-66页

作者： Bobby G Sumpter Rama K vasudevan Thomas Potok sergei v Kalinin Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTNUSA Computer Science and Mathematics Division Oak Ridge National LaboratoryOak RidgeTNUSA Institute for Functional Imaging of Materials Oak Ridge National LaboratoryOak RidgeTNUSA Computer Science and Engineering Division Oak Ridge National LaboratoryOak RidgeTNUSA

Recent technical advances in the area of nanoscale imaging,spectroscopy and scattering/diffraction have led to unprecedented capabilities for investigating materials structural,dynamical and functional *** addition,recent advances in computational algorithms and computer capacities that are orders of magnitude larger/faster have enabled large-scale simulations of materials properties starting with nothing but the identity of the atomic species and the basic principles of quantum and statistical mechanics and *** with these advances,an explosion of high-resolution data has *** confluence of capabilities and rise of big data offer grand opportunities for advancing materials sciences but also introduce several *** this perspective,we identify challenges impeding progress towards advancing materials by design(e.g.,the design/discovery of materials with improved properties/performance),possible solutions and provide examples of scientific issues that can be addressed using a tightly integrated approach where theory and experiments are linked through big-deep data.

关键词： bridge starting materials

Siberian silkmoth outbreaks surpassed geoclimatic barrier in Siberian Mountains

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Journal of Mountain Science 2020年第8期17卷 1891-1900页

作者： KHARUK viacheslav I. IM sergei T. SOLDATOv vladimir v. Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036 Russia Siberian Federal University Svobodny str.79Krasnoyarsk660041 Russia Reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk660014 Russia Russian Center of Forest Protection Academgorodok 50A/2Krasnoyarsk660036 Russia

Siberian silkmoth(SSM,Dendrolimus sibiricus Tschetv.)is the most important defoliator of Siberian pine(Pinus sibirica Du Tour)and fir(Abies sibirica Ledeb.)***-induced SSM outbreaks are one of the major driving factors of successions within the taiga *** is suggested that climate change impacted the SSM range and life *** analyzed the migration of alpine and northerly SSM outbreak boundaries in Siberia and the impact of the climate variables and topography on the outbreak *** used time-series scenes(multispectral data,and vegetation indexes EvI and NDII)in combination with field studies,climate variables,and GIS *** found that SSM outbreaks in the area of alpine boundary shifted about 370 m uphill since the mid of *** outbreak onset was promoted by increased dryness and active temperatures and decreased root zone moisture content in the spring-early summer *** terrain topography strongly affected SSM outbreak onset and ***,the outbreak was located at the middle elevations on the gentle concave southeastern slopes,which are the favorable insect habitats between *** the outbreak expanded uphill and downhill,to steeper slopes,and both concave and convex *** with elevation range expansion,SSM surpassed its northern historical outbreak boundary:the potential outbreaks’boundary moved about 300 km *** warming contributes to SSM migration into former outbreak free conifer stands located in highlands and at northern latitudes.

关键词： Insect outbreaks Remote sensing monitoring Insect ranges expansion Siberian silkmoth Forest health Conifer mortality

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振荡波导阵列中孤子的实验发现

科学通报:英文版 2023年第18期68卷 2017-2024,M0003页

作者： Antonina A.Arkhipova Yiqi Zhang Yaroslav v.Kartashov sergei A.Zhuravitskii Nikolay N.Skryabin Ivan v.Dyakonov Alexander A.Kalinkin sergei P.Kulik victor O.Kompanets Sergey v.Chekalin victor N.Zadkov Institute of Spectroscopy Russian Academy of SciencesTroitsk 108840Russia Faculty of Physics Higher School of EconomicsMoscow 105066Russia Key Laboratory for Physical Electronics and Devices(Ministry of Education) School of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Quantum Technology Centre Faculty of PhysicsM.V.Lomonosov Moscow State UniversityMoscow 119991Russia

时间参数周期变化的弗洛凯系统有助于发现常参数静态系统中不存在并常常伴有新颖拓扑态出现的非传统拓扑相.耦合系数被周期调制的Su-Schrieffer-Heeger晶格正是这种弗洛凯系统之一.尽管这个晶格在一半演化周期内处在拓扑非平庸相,在另... 详细信息

时间参数周期变化的弗洛凯系统有助于发现常参数静态系统中不存在并常常伴有新颖拓扑态出现的非传统拓扑相.耦合系数被周期调制的Su-Schrieffer-Heeger晶格正是这种弗洛凯系统之一.尽管这个晶格在一半演化周期内处在拓扑非平庸相,在另一半周期内处于拓扑平庸相,它的边界上仍然支持源于拓扑的反常π模.本文通过在透明非线性光学材料中刻蚀出周期振荡的Su-Schrieffer-Heeger波导阵列,分别实验观测到了一维系统中位于边界和二维系统中位于角落的光学反常π模.同时,在弗洛凯频谱的禁带中,作者还证实了在高功率情况下一类分化自光学反常π模的新拓扑π孤子.本文报道的π孤子是强振荡的非线性弗洛凯态,它们的波形在每经过一个纵向周期后都可以精确地复现.不论是在一维还是在二维振荡波导阵列中,这类π孤子都是动态稳定的,它们的局域特性都由其功率决定.二维的结果还表明作者实现了弗洛凯光学高阶拓扑绝缘体.

关键词： Floquet topological insulators p states Edge solitons SSH model

Machine learning for automated experimentation in scanning transmission electron microscopy

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npj Computational Materials 2023年第1期9卷 25-40页

作者： sergei v.Kalinin Debangshu Mukherjee Kevin Roccapriore Benjamin J.Blaiszik Ayana Ghosh Maxim A.Ziatdinov Anees Al-Najjar Christina Doty Sarah Akers Nageswara S.Rao Joshua C.Agar Steven R.Spurgeon Department of Materials Science and Engineering University of TennesseeKnoxvilleTN 37996USA Computational Sciences and Engineering Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Argonne National Laboratory Data Science and Learning DivisionChicagoIL 60439USA University of Chicago GlobusChicagoIL 60637USA National Security Directorate Pacific Northwest National LaboratoryRichlandWA 99352USA Department of Materials Science and Engineering Drexel UniversityPhiladelphiaPA 19104USA Department of Physics University of WashingtonSeattleWA 98195USA

Machine learning(ML)has become critical for post-acquisition data analysis in(scanning)transmission electron microscopy,(S)TEM,imaging and *** emerging trend is the transition to real-time analysis and closed-loop microscope *** effective use of ML in electron microscopy now requires the development of strategies for microscopy-centric experiment workflow design and ***,we discuss the associated challenges with the transition to active ML,including sequential data analysis and out-of-distribution drift effects,the requirements for edge operation,local and cloud data storage,and theory in the loop ***,we discuss the relative contributions of human scientists and ML agents in the ideation,orchestration,and execution of experimental workflows,as well as the need to develop universal hyper languages that can apply across multiple *** considerations will collectively inform the operationalization of ML in next-generation experimentation.

关键词： optimization automated execution

Gaussian process analysis of electron energy loss spectroscopy data:multivariate reconstruction and kernel control

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npj Computational Materials 2021年第1期7卷 1395-1404页

作者： sergei v.Kalinin Andrew R.Lupini Rama K.vasudevan Maxim Ziatdinov Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTNUSA

Advances in hyperspectral imaging including electron energy loss spectroscopy bring forth the challenges of exploratory and physics-based analysis of multidimensional data *** multivariate linear unmixing methods generally explore similarities in the energy dimension,but ignore correlations in the spatial *** the same time,Gaussian process(GP)explicitly incorporate spatial correlations in the form of kernel functions but is computationally ***,we implement a GP method operating on the full spatial domain and reduced representations in the energy *** this multivariate GP,the information between the components is shared via a common spatial kernel structure,while allowing for variability in the relative noise magnitude or image *** explore the role of kernel constraints on the quality of the reconstruction,and suggest an approach for estimating them from the experimental *** further show that spatial information contained in higher-order components can be reconstructed and spatially localized.

关键词： domain kernel multivariate

Ensemble learning-iterative training machine learning for uncertainty quantification and automated experiment in atom-resolved microscopy

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npj Computational Materials 2021年第1期7卷 909-916页

作者： Ayana Ghosh Bobby G.Sumpter Ondrej Dyck sergei v.Kalinin Maxim Ziatdinov Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTNUSA Computational Sciences and Engineering Division Oak Ridge National LaboratoryOak RidgeTNUSA

Deep learning has emerged as a technique of choice for rapid feature extraction across imaging disciplines,allowing rapid conversion of the data streams to spatial or spatiotemporal arrays of features of ***,applications of deep learning in experimental domains are often limited by the out-of-distribution drift between the experiments,where the network trained for one set of imaging conditions becomes sub-optimal for different *** limitation is particularly stringent in the quest to have an automated experiment setting,where retraining or transfer learning becomes impractical due to the need for human intervention and associated *** we explore the reproducibility of deep learning for feature extraction in atom-resolved electron microscopy and introduce workflows based on ensemble learning and iterative training to greatly improve feature *** approach allows incorporating uncertainty quantification into the deep learning analysis and also enables rapid automated experimental workflows where retraining of the network to compensate for out-of-distribution drift due to subtle change in imaging conditions is substituted for human operator or programmatic selection of networks from the *** methodology can be further applied to machine learning workflows in other imaging areas including optical and chemical imaging.

关键词： learning experiment enable

Tetramethylammonium Iodide Additive for Enhancing the Charge Carrier Mobilities of Diketopyrrolopyrrole-Based Conju-gated Polymer in Ambipolar Organic Field-Effect Transistors

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Chinese Journal of Chemistry 2023年第9期41卷 1028-1036页

作者： Waner He Qian Liu Sultan Otep Hidetoshi Matsumoto sergei Manzhos Prashant Sonar Aung Ko Ko Kyaw Tsuyoshi Michinobu Department of Materials Science and Engineering Tokyo Institute of TechnologyTokyo 152-8552Japan Guangdong University Key Laboratory for Advanced Quantum Dot Displays Department of Electrical and Electronic EngineeringSouthern University of Science and TechnologyShenzhenGuangdong 518055China Center for Materials Science School of Chemistry and PhysicsFaculty of ScienceQueensland University of TechnologyBrisbaneQLD 4000Australia School of Materials and Chemical Technology Tokyo Institute of TechnologyTokyo 152-8552Japan

Diketopyrrolopyrrole(DPP)is one of the most promising building blocks for constructing polymer semiconductors with high charge-carrier mobilities in organic field-effect transistors(OFETs).In this study,a novel DPP-based conjugated polymer,PDPPy-BDD,was designed and *** ambipolar field-effect transistor characteristics were realized with the average hole and electron mobilities of 3.5×10^(-3)and 3.07×10^(-2)cm^(2)v^(-1)s^(-1),*** the hole and electron mobilities could be successfully en-hanced by using a tetramethylammonium iodide(NMe4l)*** an enhancement was attributed to the formation of stronger interchainπ-πstackings,the weakening of the face-on packing orientation in the thin film state,and the higher channel conductivi-ties in the OFETs.

关键词： Diketopyrrolopyrrole Pyridine Charge transport Conjugated polymers Organic field-effect transistors Semiconductors Tetramethylammonium iodide Thin films

Observation of nonlinear disclination states

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Light(Science & Applications) 2023年第9期12卷 1818-1829页

作者： Boquan Ren Antonina A.Arkhipova Yiqi Zhang Yaroslav v.Kartashov Hongguang Wang sergei A.Zhuravitskii Nikolay N.Skryabin Ivan v.Dyakonov Alexander A.Kalinkin sergei P.Kulik victor O.Kompanets Sergey v.Chekalin victor N.Zadkov Key Laboratory for Physical Electronics and Devices Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Institute of Spectroscopy Russian Academy of SciencesTroitskMoscow 108840Russia Faculty of Physics Higher School of EconomicsMoscow 105066Russia Quantum Technology Centre Faculty of PhysicsM.V.Lomonosov Moscow State UniversityMoscow 119991Russia

Introduction of controllable deformations into periodic materials that lead to disclinations in their structure opens novel routes for construction of higher-order topological insulators hosting topological states at *** of these topological states is consistent with the bulk-disclination correspondence principle,and is due to the filling anomaly that results in fractional charges to the boundary unit *** far,topological disclination states were observed only in the linear regime,while the interplay between nonlinearity and topology in the systems with disclinations has been never studied *** report here on the experimental observation of the nonlinear photonic disclination states in waveguide arrays with pentagonal or heptagonal disclination cores inscribed in transparent optical medium using the fs-laser writing *** transition between nontopological and topological phases in such structures is controlled by the Kekulédistortion coefficient r with topological phase hosting simultaneously disclination states at the inner disclination core and spatially separated from them corner-I,corner-II,and extended edge states at the outer edge of the *** show that the robust nonlinear disclination states bifurcate from their linear counterparts and that location of their propagation constants in the gap and,hence,their spatial localization can be controlled by their *** disclination states can be efficiently excited by Gaussian input beams,but only if they are focused into the waveguides belonging to the disclination core,where such topological states *** results open new prospects for investigation of nonlinear effects in topological systems with disclinations and are relevant for different areas of science,including Bose-Einstein and polariton condensates,where potentials with the disclinations can be created.

关键词： structure topological nonlinear

Acoustic emission characterization of sliding wear under condition of direct and inverse transformations in lowtemperature degradation aged Y-TZP and Y-TZP-Al_2O_3

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Friction 2018年第3期6卷 323-340页

作者： Nikolai L SAvCHENKO Andrey v FILIPPOv sergei Yu TARASOv Andrey I DMITRIEv Evgeny v SHILKO Aleksandr S GRIGORIEv Institute of Strength Physics and Materials Science SB RAS National Research Tomsk Polytechnic University National Research Tomsk State University

In this research, results of the investigation of the sliding friction and wear of yttria-stabilized tetragonal zirconia polycrystalline(Y-TZP) and Y-TZP-Al_2O_3 samples preliminarily subjected to low-temperature degradation are reported. The investigation was carried out using a pin-on-disk tribometer with simultaneous recording of acoustic emission(AE) and vibration acceleration. The sliding wear process was found to be determined by dynamic direct and inverse Y-TZP transformations detected by monoclinic and tetragonal X-ray diffraction peak ratios. The AE signals generated under direct and inverse transformations can be used to characterize wear and friction mechanisms as well as direct and inversed sliding-induced phase transformations. The AE signal energy grows with the friction coefficient and the inverse transformation degree. Reduction of the AE signal energy indicates establishing the mild wear stage caused by effective stress-induced direct martensitic transformation. The AE signal median frequency increases in the case of lower friction. Numerical studies of wear subsurface fracture under conditions of stress-induced martensitic transformation were used to elucidate the role played by the phase transformation in Y-TZP and Y-TZP-Al_2O_3. Martensitic transformation in Y-TZP was described with use of the non-associated dilatant plasticity model. Simulation results particularly show that increase in the value of dilatancy coefficient from 0 to 0.2 is accompanied by 25%-30% reduce in characteristic length and penetration depth of sliding-induced subsurface cracks. As shown the AE may be an effective tool for in-situ monitoring the subsurface wear of materials experiencing both direct and inverse transformations.

关键词：摩擦仪表面磨损摩擦学物理性能