检索结果-南通市图书馆

Coexisting charge density wave and ferromagnetic instabilities in monolayer inSe

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2022年第1期8卷 1101-1109页

作者： Evgeny A.Stepanov Viktor Harkov Malte Rösner Alexander i.Lichtenstein mikhail i.katsnelson Alexander N.Rudenko CPHT CNRSEcole PolytechniqueInstitut Polytechnique de ParisF-91128PalaiseauFrance i.institute of Theoretical Physics University of HamburgNotkestraße 922607HamburgGermany European X-Ray Free-Electron Laser Facility Holzkoppel 422869SchenefeldGermany Radboud University Institute for Molecules and Materials6525AJNijmegenThe Netherlands The Hamburg Centre for Ultrafast imaging Luruper Chaussee 14922761HamburgGermany

Recently fabricated inSe monolayers exhibit remarkable characteristics that indicate the potential of this material to host a number of many-body *** this work,we systematically describe collective electronic effects in hole-doped inSe monolayers using advanced many-body *** this end,we derive a realistic electronic-structure model from first principles that takes into account the most important characteristics of this material,including a flat band with prominent van Hove singularities in the electronic spectrum,strong electron–phonon coupling,and weakly screened long-ranged Coulomb *** calculate the temperature-dependent phase diagram as a function of band filling and observe that this system is in a regime with coexisting charge density wave and ferromagnetic instabilities that are driven by strong electronic Coulomb *** regime can be achieved at realistic doping levels and high enough temperatures,and can be verified *** find that the electron–phonon interaction does not play a crucial role in these effects,effectively suppressing the local Coulomb interaction without changing the qualitative physical picture.

关键词： ferromagnetic charge wave

Electron correlation effects on exchange interactions and spin excitations in 2D van der Waals materials

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2021年第1期7卷 33-40页

作者： Liqin Ke mikhail i.katsnelson Ames Laboratory U.S.Department of EnergyAmesIowa 50011USA institute for Molecules and Materials Radboud UniversityHeijendaalseweg 1356525AJ NijmegenThe Netherlands

Despite serious effort,the nature of the magnetic interactions and the role of electron-correlation effects in magnetic twodimensional(2D)van der Waals materials remains *** Cri3 as a model system,we show that the calculated electronic structure including nonlocal electron correlations yields spin excitations consistent with inelastic neutron-scattering ***,this approach identifies an unreported correlation-enhanced interlayer super-superexchange,which rotates the magnon Dirac lines off,and introduces a gap along the high-symmetryΓ-K-M *** discovery provides a different perspective on the gap-opening mechanism observed in Cri3,which was previously associated with spin–orbit coupling through the Dzyaloshinskii–Moriya interaction or Kitaev *** observation elucidates the critical role of electron correlations on the spin ordering and spin dynamics in magnetic van der Waals materials and demonstrates the necessity of explicit treatment of electron correlations in the broad family of 2D magnetic materials.

关键词： interaction materials excitation

Dodecagonal bilayer graphene quasicrystal and its approximants

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2019年第1期5卷 73-82页

作者： Guodong Yu Zewen Wu Zhen Zhan mikhail i.katsnelson Shengjun Yuan Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education and School of Physics and Technology Wuhan UniversityWuhan 430072China institute for Molecules and Materials Radboud UniversityHeijendaalseweg 135NL-6525 AJ NijmegenNetherlands

Dodecagonal bilayer graphene quasicrystal has 12-fold rotational order but lacks translational symmetry which prevents the application of band *** this paper,we study the electronic and optical properties of graphene quasicrystal with large-scale tight-binding calculations involving more than ten million *** propose a series of periodic approximants which reproduce accurately the properties of quasicrystal within a finite unit *** utilizing the band-unfolding method on the smallest approximant with only 2702 atoms,the effective band structure of graphene quasicrystal is *** features,such as the emergence of new Dirac points(especially the mirrored ones),the band gap at M point and the Fermi velocity are all in agreement with recent *** properties of quasicrystal states are identified in the Landau level spectrum and optical ***,our results show that the lattice mismatch is the dominant factor determining the accuracy of layered *** proposed approximants can be used directly for other layered materials in honeycomb lattice,and the design principles can be applied for any quasi-periodic incommensurate structures.

关键词： theory. layered periodic

importance of charge self-consistency in first-principles description of strongly correlated systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2021年第1期7卷 1949-1956页

作者： Swagata Acharya Dimitar Pashov Alexander N.Rudenk Malte Rösner Mark van Schilfgaarde mikhail i.katsnelson institute for Molecules and Materials Radboud UniversityNijmegen 6525 AJThe Netherlands Theory and Simulation of Condensed Matter King's College LondonThe StrandLondon WC2R2LSUK National Renewable Energy Laboratory Golden80401 ColoradoUSA

First-principles approaches have been successful in solving many-body Hamiltonians for real materials to an extent when correlations are weak or *** the electronic correlations become stronger often embedding methods based on first-principles approaches are used to better treat the correlations by solving a suitably chosen many-body Hamiltonian with a higher level *** success of such embedding theories,often referred to as second-principles,is commonly measured by the quality of self-energy E which is either a function of energy or momentum or ***,E should,in principle,also modify the electronic eigenfunctions and thus change the real space charge *** such practices are not prevalent,some works that use embedding techniques do take into account these *** such cases,choice of partitioning,of the parameters defining the correlated Hamiltonian,of double-counting corrections,and the adequacy of low-level Hamiltonian hosting the correlated subspace hinder a systematic and unambiguous understanding of such ***,for a large variety of correlated systems,strong correlations are largely confined to the charge *** an adequate non local low-order theory is important,and the high-order local correlations embedding contributes become *** we study the impact of charge self-consistency within two example cases,TiSez and CrBrs,and show how real space charge re-distribution due to correlation effects taken *** within a first-principles Green's function-based many-body perturbative approach is key in driving qualitative changes to the final electronic structure of these materials.

关键词： theory charge principles

Egypt Shows World How to Tackle Hepatitis C

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Engineering 2024年第7期38卷 2-4页

作者： Alla katsnelson Senior Technology Writer

in October 2023,Egypt received recognition for a feat that cheered public health experts around the world:it became the first country awarded the World Health Organization(WHO)“Gold Tier”certification for its progress in eliminating viral hepatitis caused by the hepatitis C virus(HCV)[1].it is also the first time in history that a country has nearly eliminated a chronic illness caused by a *** that achievement itself is remarkable,especially impressive is the speed with which Egypt accomplished this public health *** just 14 years,from 2008 to 2022,Egypt’s prevalence of HCV viral hepatitis fell from 10%to 0.38%[1],and deaths due to the disease dropped by 51%[2].Modeling suggests the country’s aggressive elimination program,which has tested more than 60 million people and treated more than 4 million[1],will have prevented almost 250000 HCV-related deaths by 2030[3].

关键词： Egypt eliminating eliminated

Environmental screening and ligand-field effects to magnetism in Cri_(3) monolayer

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2021年第1期7卷 1481-1490页

作者： D.Soriano A.N.Rudenko M.i.katsnelson M.Rösner Radboud University Institute for Molecules and MaterialsHeyendaalseweg 1356525 AJ NijmegenThe Netherlands Universitàdi Pisa Dipartimento di Ingegneria dell’InformazioneVia Caruso56122 PisaItaly Department of Theoretical Physics and Applied Mathematics Ural Federal University620002 EkaterinburgRussia

We study the microscopic origin of magnetism in suspended and dielectrically embedded Cri_(3)monolayer by down-folding minimal generalized Hubbard models from ab initio calculations using the constrained random phase *** models are capable of describing the formation of localized magnetic moments in Cri_(3)and of reproducing electronic properties of direct ab initio *** the magnet force theorem,we find a multi-orbital super-exchange mechanism as the origin of magnetism in Cri_(3)resulting from an interplay between ferro-and anti-ferromagnetic Cr-Cr d coupling channels,which is decisively affected by the ligand p *** show how environmental screening,such as resulting from encapsulation with hexagonal boron nitride,affects the Coulomb interaction in the film and how this controls its magnetic *** by a non-monotonic interplay between nearest and next-nearest neighbor exchange interactions we find the magnon dispersion and the Curie temperature to be non-trivially affected by the environmental screening.

关键词： properties monolayer exchange

Geoacoustic inversion Using Time Reversal of Ocean Noise

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2017年第9期34卷 62-65页

作者：秦继兴 Boris katsnelson Oleg Godin 李整林 State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190 Department of Marine Geosciences School of Marine SciencesUniversity of HaifaHaifa 31905Israel Cooperative institute for Research in EnvironmentM Sciences University of Colorado BoulderColorado 80309 USA

We present a passive geoacoustic inversion method using two hydrophones, which combines noise interferometry and time reversal mirror （TRM） techniques. Numerical simulations are firstly performed, in which strong fo- cusing occurs in the vicinity of one hydrophone when Green＇s function （GF） is back-propagated from the other hydrophone, with the position and strength of the focus being sensitive to sound speed and density in the bottom. We next extract the GF from the noise cross-correlation function measured by two hydrophones with 8025-m distance in the Shallow Water ＇06 experiment. After realizing the TRM process, sound speed and density in the bottom are inverted by optimizing focusing of the back-propagated GF. The passive inversion method is inherently environmentally friendly and low-cost.

关键词： Geoacoustic inversion Using Time Reversal of Ocean Noise GF

New Hope for HiV Microbicide

在线全文

学校读者我要写书评

暂无评论

科技英语学习 2009年第6期 16-18页

作者： Alla katsnelson 林波

最近出版的《自然》杂志报道说，最新的艾滋病研究发现，一种在化妆品和食品行业广泛应用的合成物质——甘油一月桂酸酯——可以有效阻止艾滋病的传播。研究人员将该化学物质制成溶剂，其药效已在猴子实验中得到了一定的证实，但它是否... 详细信息

最近出版的《自然》杂志报道说，最新的艾滋病研究发现，一种在化妆品和食品行业广泛应用的合成物质——甘油一月桂酸酯——可以有效阻止艾滋病的传播。研究人员将该化学物质制成溶剂，其药效已在猴子实验中得到了一定的证实，但它是否能够推而广之运用在人类身上，仍需进一步的实验研究。

关键词：艾滋病化学物质研究预防 HiV

在线全文

学校读者我要写书评

暂无评论

浅海中孤立子内波引起的声能量起伏

声学学报 2016年第2期41卷 145-153页

作者：秦继兴 katsnelson Boris 李整林张仁和骆文于中国科学院声学研究所声场声信息国家重点实验室北京100190 Department of Marine Geosciences School of Marine Sciences University of Haifa 中国科学院声学研究所南海研究站海口570105

当孤立子内波的波阵面与声传播路径所成角度较大时,简正波耦合是导致声信号起伏的主要因素。研究了浅海中孤立子内波引起的声能量起伏规律,给出声场起伏的耦合简正波表达式,并使用抛物方程模型进行仿真。数值分析表明,接收点声强随时间... 详细信息

当孤立子内波的波阵面与声传播路径所成角度较大时,简正波耦合是导致声信号起伏的主要因素。研究了浅海中孤立子内波引起的声能量起伏规律,给出声场起伏的耦合简正波表达式,并使用抛物方程模型进行仿真。数值分析表明,接收点声强随时间变化呈准周期性。在频谱图中能够得到声强起伏的主导频率,主导频率与孤立子内波沿声传播路径的移动速度成正比,与无扰动波导中简正波在距离上的干涉周期(对应于射线理论中临界声线的跨度)成反比,与孤立子内波的形状无关。此外,对声强频谱的垂直结构进行了分析,该结构与对声场起伏起主要作用简正波的本征函数相关。

关键词：孤立子内波信号起伏声能量浅海传播路径准周期性主导频率垂直结构