检索结果-南通市图书馆

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

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 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： Ji-Xing Qin Boris katsnelson Oleg Godin Zheng-Lin Li 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

Dodecagonal bilayer graphene quasicrystal and its approximants

维普期刊数据库

同方期刊数据库评论

在线全文

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

脑缺氧是影响严重颅脑创伤患者短期预后的独立危险因素(英文)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中华神经外科疾病研究杂志 2011年第5期10卷 452-452页

作者： Oddo m Levine Jm mackenzie L Frangos S Feihl F Kasner SE katsnelson m Pukenas B macmurtrie E maloney-Wilensky E Kofke WA Leroux PD

Background:Brain hypoxia(BH)can aggravate outcome after severe traumatic brain injury(TBI).Whether BH or reduced brain oxygen(Pbto2)is an independent outcome predictor or a marker of disease severity is not fully *** To analyze the relationship between Pbto2,intracranial pressure(ICP),and cerebral perfusion pressure(CPP)and to examine whether BH correlates with worse outcome independently of ICP and *** We studied103patients

关键词：脑缺氧颅脑创伤短期预后危险因素

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

维普期刊数据库

同方期刊数据库评论

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 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

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