【直播】2022材料多尺度计算模拟国际会议

由中国材料研究学会计算材料学分会主办的“材料多尺度计算模拟国际会议”旨在为国内外科研工作者提供一个交流和展示多尺度计算模拟领域最新进展及成果的平台，促进材料多尺度计算模拟的发展，推动计算材料学领域内的学术进步以及相关行业的发展。经过多年的努力，材料多尺度计算模拟国际会议已经成为计算材料科学领域有影响力的国际会议之一。迄今为止，该会议已成功举办了13次。第14届材料多尺度计算模拟国际会议将于2022年7月4日-8日在成都举行，由电子科技大学承办，将围绕新型自旋电子材料及其输运特性、多体系统的量子理论与计算、高效能源转存材料与器件设计、拓扑电子态与拓扑磁性等方向的议题开展研讨。
组委会诚邀海内外相关领域的专家学者及企业界人士参会交流。相约成都，共创未来。

直播信息

会议名称

2022材料多尺度计算模拟国际会议

会议时间

2022年7月4-8号

组织机构

主办单位：中国材料研究学会计算材料学分会

承办单位：电子科技大学

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会议安排

会议主题

1. 新型自旋电子材料及其输运特性

New spintronic materials and their transport properties

2. 光、声、电多场耦合效应的多尺度模拟

Multi-field simulations on the coupling effects of light, phonon and electricity

3. 多体系统的量子理论与计算

Quantum theory and computation of many-body systems

4、高效能源转存材料与器件设计

Advanced materials and devices for energy conversation

5、高性能结构材料

High-performance structural materials

6、拓扑电子态与拓扑磁性

Topological states and topological magnetism

7、机器学习及其在新材料预测与设计中的应用

Machine learning and its applications in the prediction and design of new materials

报告人介绍

报告题目：Negative Force Constant Manifested by Topological Phonons

报告人简介：

Feng Liu, Distinguished and Ivan B. Cutler Professor of Department of Materials Science and Engineering, University of Utah. He received his PhD in Chemical Physics from Virginia Commonwealth University in 1990. Prof. Liu is a fellow of American Physical Society and recipient of Senior Humboldt Award. His research interest lies in theoretical and computational studies of low-dimensional nano and quantum materials, with a most recent focus on topological and flat-band materials.

报告摘要：
Phonons as bosons have notably fundamental differences from electrons as fermions. Unlike interatomic electron hopping that can be either positive or negative, interatomic force constant must be positive, otherwise the atomic structure would be unstable without restoring forces. Strikingly, we demonstrate that multi-atom cluster-mode vibrations can be coupled with a negative force constant (NFC), which is in fact a direct physical manifestation of topological phonons. Using the spring-mass lattice model, we show that topological phonon flat band (FB), in analogy of topological electron FB hosted in line-graph lattices, can have either a positive or negative Chern number manifesting a positive FC or NFC, respectively; while a phononic topological insulator, characterized with “mode inversion” around a phonon Dirac point, implies always an NFC. Guided by this fundamental correspondence between NFC and nontrivial phonon topology, we perform first-principles calculations and model analyses to elucidate the existence of phonon FB of NFC in a real material of 2D Kagome-BN. Our work presents a conceptual advance in understanding topological phonons in association with NFC, which can be generalized to meta-materials to generate topological mechanical and sound waves by engineering negative compressibility.

报告题目：New Functionalities in Low-dimensional Magnetic Materials

报告人简介：

Ruqian Wu, professor of physics and astronomy at the University of California, Irvine (UCI). His primary research area is condensed matter physics.He gained a Ph.D. at the Institute of Physics, Academia Sinica. He was awarded the status of Fellow in the American Physical Society, after he was nominated by their Division of Computational Physics in 2001, for contributions to the understanding of magnetic, electronic, mechanical, chemical and optical properties of compounds, alloys, interfaces, thin films and surfaces using first-principles calculations and for development of the methods and codes for such components.

https://en.wikipedia.org/wiki/Ruqian_Wu

报告摘要：
Using density functional approach and model simulations, physical properties of many systems can be reliably predicted and explained. In this talk, I will discuss examples of our recent theoretical studies of low-dimensional magnetic materials, from quantum spin states of magnetic molecules to the magnetic topological materials. More explicitly, I will discuss the effect of spin-vibration coupling on spin decoherence in small systems such as single magnetic molecule or atom. For topological materials, I will focus on the manipulation of corner states of high order topological insulators with magnetic and electric fields. Some results will be discussed along with experimental data from collaborators.

报告题目：Ab Initio Quantum Dynamics in Nanoscale Materials

报告人简介：Oleg Prezhdo obtained Diploma in Theoretical Chemistry from Kharkiv University, Ukraine, in the theory group originating from V. A. Fock. He completed PhD within 4 years with Peter Rossky at UT-Austin. After a 1-year postdoc with John Tully at Yale, he joined University of Washington in 1998, achieving Associate and Full Professor in 2002 and 2005. In 2010 he was offered Senior Professorship at University of Rochester, and in 2014 moved to University of Southern California, where he is Professor of Chemistry, Physics & Astronomy, and Chemical Engineering. He served as an Editor in the Journal of Physical Chemistry and Surface Science Reports. Currently, he is an Executive Editor for the Journal of Physical Chemistry Letters. Recipient of multiple national and international awards, he held visitor positions and professorships in France, Germany, Spain, Ukraine, Japan, China and Luxembourg. With about 500 papers, 400 invited talks, and h-index of 87, his research interests range broadly from semiclassical physics and time-dependent density functional theory, to quantum dynamics and far-from-equilibrium processes in nanoscale, condensed matter, molecular and biological systems.
报告摘要：
Excited state dynamics play key roles in numerous novel molecular and nanoscale materials designed for optoelectronics and energy applications. Controlling these far-from-equilibrium processes and steering them in desired directions require understanding of material’s dynamical response on the nanometer scale and with fine time resolution. We couple real-time time-dependent density functional theory for the evolution of electrons with non-adiabatic molecular dynamics for atomic motions to model such non-equilibrium response in the time-domain and at the atomistic level. The talk will describe the basics of the simulation methodology and discuss exciting applications among the broad variety of systems and processes studied in our group, including metal halide perovskites, transition metal dichalcogenides, semiconducting and metallic quantum dots and films, polymers, molecular crystals, graphene, carbon nanotubes, etc. Photo-induced charge and energy transfer, plasmonic excitations, Auger-type processes, energy losses and charge recombination create many challenges due to large differences between molecular and periodic, and organic and inorganic matter. Our simulations provide a unifying description of quantum dynamics on the nanoscale, characterize the timescales and branching ratios of competing processes, resolve debated issues, and generate theoretical guidelines for development of novel systems.

报告题目：In the quest for excited states, from machine learning to non-adiabatic dynamics

报告人简介：

Sergei Tretiak is a T-1 deputy group Leader in the Theoretical Division at Los Alamos National Laboratory (LANL) and a Los Alamos National Laboratory Fellow. He received his Master’s degree in Physics in 1994 from Moscow Institute of Physics and Technology (Russia) and his Chemistry doctorate in 1998 from the University of Rochester (US). He was then a Director-funded postdoctoral fellow (1999-2001), and subsequently became a staff scientist at LANL and a member of the DOE-funded Center for Integrated Nanotechnologies (CINT). Tretiak also serves as Adjunct Professor at the University of California, Santa Barbara (UCSB) (2015-present). He became an American Physical Society Fellow (APS) in 2014 and a Fellow of the Royal Society of Chemistry, (RSC) in 2019. He has also received the Humboldt Research Award (2021), the Los Alamos Postdoctoral Distinguished Mentor Award (2015) and the Los Alamos Fellow's Prize for Research (2010). His research interests include development of electronic structure methods for molecular optical properties, nonlinear optical response of organic chromophores, non-adiabatic dynamics of electronically excited states, optical response of confined excitons in conjugated polymers, carbon nanotubes, semiconductor nanoparticles, mixed halide perovskites and molecular aggregates, the use of Machine Learning and Data Science toward modeling electronic and chemical properties. Tretiak has published nearly 400 scientific publications cited more than 22,000 times (h-index=71, WebOfSci) and he has presented more than 300 invited and keynote talks in the US and abroad.

报告摘要：
Machine learning (ML) is quickly becoming a premier tool for modeling chemical processes and materials. Designing high-quality training data sets is crucial to overall model accuracy. I will describe the active learning strategy, in which new data are automatically collected for atomic configurations that produce large ML uncertainties. The locality approximation underpinning favorable computational scaling of the ML models, is another severe limitation that fails to capture long-range effects. I will discuss how ML models can overcome nonlocality (via introduction of interaction layers, self-consistent cycles, or charge equilibration schemes) and exemplify their performance for chemical problems. All these advances are exemplified by applications to molecules and materials. Exciting new method development and explosive growth of user-friendly ML frameworks, designed for chemistry, demonstrate that the field is evolving towards physics-based models augmented by data science. I will further overview some applications of Non-adiabatic EXcited-state Molecular Dynamics (NEXMD) framework developed at several institutions. The NEXMD code is able to simulate tens of picoseconds photoinduced dynamics in large molecular systems. As an application, I will exemplify ultrafast coherent excitonic dynamics guided by intermolecular conical intersections (CoIns). Both simulations and time-resolved 2D electronic spectroscopy track the coherent motion of a vibronic wave packet, a process that governs the ultrafast energy transfer dynamics in molecular aggregates. Our results suggest that intermolecular CoIns may effectively steer energy pathways in functional nanostructures. In the second example, we use NEXMD simulations to compute X-ray Raman signals, which are able to sensitively monitor the coherence evolution. The observed coherences have vibronic nature that survives multiple conical intersection passages for several hundred femtoseconds at room temperature. These spectroscopic signals are possible to measure at XFEL facilities. Our modeling results allow us to understand and potentially manipulate excited state dynamics and energy transfer pathways toward optoelectronic applications.

报告题目：Large scale atomistic material simulations:the challenges and opportunities.

报告人简介：
Chief scientist in Semiconductor Institute, CAS, and chief scientific advisor in LongXun Kuang Teng Inc. Senior Staff Scientist, Lawrence Berkeley National Laboratory, Berkeley, CA, U.S. 1999-2021. Dr. Wang has 30 years of experience in large scale electronic structure calculations. He has worked in O(N) electronic structure calculations in early 1990s. Worked with Alex Zunger, he invented the folded spectrum method which pushed the limit of nonselfconsistent electronic structure calculations from 100 atoms to thousands of atoms. He developed a linear combination of bulk bands (LCBB) method for semiconductor heterostructrure electronic structure calculations, which allows the calculation of million atom devices. He developed generalized moments method which calculates the density of state and optical absorption spectra of a given system without explicit calculation of its eigenstates. He also developed a popular parallel total energy plane wave pseudopotential program (PEtot). He invented a charge patching method, which enables the ab initio accuracy thousand atom calculations for nanosystems. He has developed a linear scaling three dimensional fragment method (LS3DF), which can be used to selfconsistently calculate systems with tens of thousands of atoms. Recently, he developed a new algorithm for real-time time-dependent DFT calculations which accelerates the traditional algorithms by hundreds of times.
报告摘要：
The ab initio material simulation based on quantum mechanics has been developed for more than forty years. With the maturity of the methods, the developments of user friendly codes, and the increase of high performance computer power, the atomistic ab initio methods, especially the methods based on density functional theory, have been used in every aspects of material researches. It is now a common practice to simulate systems with hundreds of atoms. However, since the computational cost scales as the third power of the number of atoms, new strategies are needed to go beyond this barrier. Furthermore, hug gap exists between the computable systems and many of the experimental systems, both in size scale and temporal scale. How to bridge this gap is a main challenge in order to bring the ab initio computation into industry. To overcome such challenges, we need to use multiple methods, including linear scaling method, machine leaning method, as well as kinetic Monte Carlo schemes to overcome the time scales.

报告题目：Skyrmion Size in Skyrmion Crystals

报告人简介：

Professor Wang obtained his BA degree (1980) from Wuhan University and his ScM (1986) and PhD (1990) degrees from University of Rochester. He was awarded Minnesota Supercomputer Institute Fellow (1991) for post-doctoral studies at the University of Minnesota. He joined the Physics Department of HKUST in 1992.

Professor Wang is interested in revealing the physics principles behind the novel physics phenomena in condensed matter physics. Currently, he is working on the interplay of charges, spins, and phonons in interesting materials and devices. One particular question is how the interactions of charge, spin, and phonons affect the spin dynamics and electron transport. The current research topics include magnetic domain wall motion under electric and magnetic fields, thermal gradient, and spin current of electrons and magnons; domain wall pinning theory; theories for large magnetoresistance in nonmagnetic systems; and electronic properties of novel systems.

https://physics.ust.hk/eng/people_detail.php?id=22&pplcat=1

报告摘要：
A magnetic skyrmion can be in an isolated form or in a condensate form. Each skyrmion in a condensed phase takes a stripe shape at low skyrmion density and a circular shape at high skyrmion density. Skyrmions at high density form a skyrmion crystal (SkX). In this talk, we will see that skyrmion size in a SkX has a different parameter dependence as those for isolated skyrmions and stripes. A size formula and a good spin profile for skyrmions in SkXs are proposed. These findings have important implications in searching for stable smaller skyrmions at the room temperature.

报告题目：The design of topological states under light irradiation

报告人简介：王锐，重庆大学物理学院物理系教授。研究方向为：计算凝聚态物理，拓扑材料的性质研究和设计，缺陷物理，拓扑量子态的输运性质研究，无序凝聚态体系。长期从事计算凝聚态物理研究，通过理论建模与数值计算，并结合对称性分析、有效介质理论、紧束缚模型等方法，围绕固体拓扑缺陷、拓扑电子材料、拓扑声子材料的理论设计与量子调控等科学问题开展了一系列研究，相关研究成果发表在Phys. Rev. Lett.等级期刊, 包括4篇Phys. Rev. Lett.、20余篇Phys. Rev. B (其中11篇为PRB Rapid Commun.或Letter)，研究成果引起了国内外同行的广泛关注和肯定，部分研究结果已得到实验验证或者国际同行采用。主持国家自然基金项目3项，曾获得教育部博士学术新人奖，入选重庆市青年拔尖人才，担任了国际著名期刊Nature Communications, Phys. Rev. Lett.等审稿人，被聘为Front. Phys.客座编辑。担任本科生专业课《热学》、公共基础课《大学物理》、以及物理学院研究生《固体能带理论》、《凝聚态物理》等课程教学；长期担任全国大学生物理学术竞赛教练，第4、5、6、7届全国大学物理物理学术竞赛裁判；已培养多名研究生获得研究生国家奖学金、获国际Maxwell Prize 提名等。
http://phys.cqu.edu.cn/info/1133/3619.htm

报告摘要：
The investigation of the topological phase of matter has been a major subject in condensed matter physics. Beyond static topological systems, the exploration of topological phases has been dynamically extended to systems that are driven periodically out of equilibrium. The periodic driving breaks the time-translation symmetry and thus leads to unique nonequilibrium Floquet engineering of topological phases. Here, based on Floquet theory, effective model approach, and first-principles calculations, we introduce our recent studies on the design of promising topological states in a periodically driven system, such as photoinduced quantum anomalous Hall states and higher-order topological states .

报告题目：Polaron Dynamics in Metal Oxide Photocatalysts from a Theoretical Perspective

报告人简介：龙闰，北京师范大学化学学院教授，Journal of Physical Chemistry Letters副主编，目前研究兴趣集中在凝聚相材料激发态动力学。

报告摘要：
Polarons are formed by a local distortion of the lattice that creates a self-trapping potential for the charge carrier, which play a major role in changing the charge carrier mobility and chemical reactivity of transition metal oxides. Using a combination of ab initio molecular dynamics, time-dependent density functional theory, and nonadiabatic molecular dynamics, we have demonstrated that polaron formation and recombination in Fe2O3 [1], how the interaction between CO and polarons alters the TiO2 photoacitivity [2], and how polarons regulate the desorption and dissociation of an adsorbed O2 atop a reduced TiO2(110) surface [3]. The detailed atomistic knowledge obtained from the explicit time-domain modeling generates comprehensive understanding of charge-phonon dynamics in metal oxides photocatalysts, and leads to valuable guidelines for improvement of novel systems for photocatalysts.

报告题目：拓扑金属材料的量子输运

报告人简介：孙岩，中科院金属所研究员，博导， 国家级青年人才项目获得者，Web of Science高被引学者。主要研究兴趣是结合对称分析和电子能带结构对材料量子响应的理论和计算，并于实验保持密切合作。代表工作有：理论预测首个被实验证实的二类外尔半金属、与量子输运实验合作提出了首个直接被观测到的磁性外尔半金属、首次预测外尔半金属和节线半金属中强自旋霍尔效应、建立首个自旋电子学材料完备数据库、首次从体态波函数的角度提出化学析氢催化材料描述符。迄今在Science, Nature, Nat. Phys., Nat. Mater., Adv. Mater.，npj Comput. Mater., PRL, PBR等发表论文100多篇，被引超过9500次。

报告摘要：对称和电子能带结构的结合曾经发现了材料中各种物理响应，其中量子化和强化的物理响应经常伴随着一些拓扑的特征。外尔点和节线能带结构的贝利曲率对线性响应具有明显的增强作用。通过对外尔半金属和节线半金属线性响应的研究，我们发现了其中的强自旋霍尔效应、自旋能斯特效应，反常霍尔效应和反常能斯特效应。镜面对称保护的节线能带结构为金属铂中的强自旋霍尔效应给出了一个清晰的理解。结构和对称分析和高通量计算，发现反常霍尔电流并不需要服从传统的理解，平带结构与拓扑能带结构的结合，对线性响应具有进一步增强的效果。通过这种结合我们提出了f电子系统中的强反常霍尔效应，并直接被实验观测到。在非线性光学中，为了判定好的二阶光伏材料，我们结合体态光伏理论和太阳辐射提出了太阳能整流向量，其可以类比于p-n节太阳能电池中的Shockley-Queisser模型。除了强物理响应信号，我们提出了利用二阶响应信号判定手性拓扑半金属材料的手性和其对应波函数的相位。

报告题目：Twisted magnon frequency comb and Penrose superradiance

报告人简介： 

严鹏，电子科技大学, 电子科学与工程学院(原微电子与固体电子学院), 校百人计划特聘教授。长期担任Physical Review Letters, Physical Review X, Physical Review Applied, Physical Review B, New Journal of Physics等国际学术期刊审稿人。2015年担任国际磁学会议(IEEE Intermag)分会主席。2013年担任戈登会议"Spin Dynamics in Nanostructures"海报分会主席。2012年担任德国雷根斯堡大学"热激发自旋电子学学术研讨会"大会组织者兼大会主席。德国科学基金会（DFG）优先项目"热激发自旋输运"指委会委员。研究方向为：自旋电子学 (Spintronics)与热激发自旋电子学 (Spin caloritronics), 自旋波 (Spin wave), 微磁学与磁动力学 (Magnetization dynamics), 腔量子电动力学 (Cavity quantum electrodynamics), 非平衡态热力学与统计 (Nonequilibrium thermodynamics and statistics), 生物磁性与磁导航(Biomagnetism and navigation)

报告摘要：
Quantization effects of the nonlinear magnon-vortex interaction in ferromagnetic nanodisks are studied. We show that the circular geometry twists the spin-wave fields with spiral phase dislocations carrying quantized orbital angular momentum (OAM). Meanwhile, the confluence and splitting scattering of twisted magnons off the gyrating vortex core (VC) generates a frequency comb consisting of discrete and equally spaced spectral lines, dubbed as twisted magnon frequency comb (tMFC). It is found that the mode spacing of the tMFC is equal to the gyration frequency of the VC and the OAM quantum numbers between adjacent spectral lines differ by one. By applying a magnetic field perpendicular to the plane of a thick nanodisk, we observe a magnonic Penrose superradiance inside the cone vortex state, which mimics the amplification of waves scattered from a rotating black hole. It is demonstrated that the higher-order modes of tMFC are significantly amplified while the lower-order ones are trapped within the VC gyrating orbit which manifests as the ergoregion. These results suggest a promising way to generate twisted magnons with large OAM and to drastically improve the flatness of the magnon comb.

报告题目：Magic-angle twisted bilayer graphene as a topological heavy fermion problem

报告摘要：
Magic-angle (θ = 1:05◦) twisted bilayer graphene (MATBG) has shown two seemingly contradictory characters: the localization and quantum-dot-like behavior in STM experiments, and delocalization in transport experiments. We construct a model, which naturally captures the two aspects, from the Bistritzer-MacDonald (BM) model in a first principle spirit. A set of local flat-band orbitals (f) centered at the AA-stacking regions are responsible to the localization. A set of extended topological semi-metallic conduction bands (c), which are at small energetic separation from the local orbitals, are responsible to the delocalization and transport. The topological flat bands of the BM model appear as a result of the hybridization of f- and c-electrons. This model then provides a new perspective for the strong correlation physics, which is now described as strongly correlated f-electrons coupled to nearly free c-electrons - we hence name our model as the topological heavy fermion model. Using this model, we obtain the U(4) and U(4)×U(4) symmetries as well as the correlated insulator phases and their energies. Simple rules for the ground states and their Chern numbers are derived. Moreover, features such as the large dispersion of the charge ±1 excitations, and the minima of the charge gap at the ΓM point can now, for the first time, be understood both qualitatively and quantitatively in a simple physical picture. Our mapping opens the prospect of using heavy-fermion physics machinery to the superconducting physics of MATBG.

报告题目：新型光电半导体材料设计

报告人简介：张立军，吉林大学材料科学与工程学院教授&博士生导师。长期聚焦半导体光电材料，应用自主研发的材料设计方法与软件JAMIP (http://www.jamip-code.com)，开展新材料设计与光电性能调控研究，多个从理论上设计的新材料与新性能调控策略得到实验证实。自2014年回国，作为第一/通讯作者在Nat. Rev. Mater., Nat. Photonics, Nat. Commun., Phys. Rev. Lett., J. Am. Chem. Soc., Adv. Mater.等期刊发表论文80余篇，所有论文共被引用12650次，H因子55。先后入选国家海外高层次青年人才引进计划（2014），主持基金委优秀青年基金（2017）及杰出青年基金（2021）项目。获中国材料研究学会“计算材料学青年奖”、吉林省青年科技奖—特别奖。受邀在美国材料研究学会春季会议、欧洲材料研究学会春季会议、新加坡先进技术材料国际会议等国际国内会议上做特邀报告60余次。

报告摘要：
具有一定带隙的半导体材料在光电领域中被广泛应用，例如太阳能电池、光电探测、发光二极管及光催化等。随着超级计算机计算能力的显著增强以及人工智能、机器学习算法的不断发展，人们通过材料模拟，只需花费实验研究所需时间的一小部分，就可以探索巨大数量候选功能材料的特性。这使得功能导向的新材料设计在计算机模拟中得以实现。在这里，我将主要汇报我们近期在新型半导体光电材料的优化设计方面开展的工作。具体内容包括我们发展的具有自主知识产权的材料设计方法与软件JAMIP（全称Jilin Artificial-intelligence aided Materials-design Integrated Package，http://www.jamip-code.com，软件著作权：2021SR0349238）及应用其在太阳能光伏材料、透明导体材料、光电探测材料、光催化材料等光电半导体体系开展的新材料设计研究；部分理论设计的材料已得到实验证实并应用于光电器件。

报告题目：机器学习与高通量计算在电催化剂开发中的应用

报告人简介：张旭，现为郑州大学化工学院直聘研究员，多年来致力于结合理论计算与机器学习研究二维无机催化材料。研究揭示了MXene等多种二维材料的物理化学特性和潜在应用，部分结果为实验验证；发展了层状和二维材料高通量筛选方法，筛选了钠离子电池材料和光解水催化剂；通过数据库与机器学习结合设计了多种单原子电催化剂。

报告摘要：
对催化重要能源转化过程电催化剂的高效研发是实现可持续发展的必然需求。利用传统实验“试错法”研究往往受限于长周期、高成本，从而难以满足当今社会发展速度的需求。近年来，结合机器学习与高通量计算的研究方法在电催化剂的开发领域中展现出活力，并逐渐成为新型催化剂研究的有力工具。基于以上背景，本课题组结合机器学习与高通量计算，从高效电催化剂筛选、理性设计及电催化机理探索等方面进行研究，以期借此新的研究方法推动电催化剂的发展，并缩小理论计算与实验之间的鸿沟。

报告题目：能带色散关系与空间维度对狄拉克材料中光电导的影响

报告人简介：
四川师范大学物理系、计算科学中心和固体物理研究所副教授。2012年从中国科学技术大学获得博士学位，随后进入四川师范大学工作，2017年-2018年在加拿大McGill大学访问。主要研究兴趣为理论凝聚态物理和量子场论。在理论凝聚态物理方面，近期主要关注拓扑半金属、硅烯、单层过渡金属二硫化物等拓扑材料中的新奇物理性质，包括集体激发、光电性质、输运性质和磁性相互作用等。在量子场论方面，近期主要关注与广义Kramers-Kronig关系、广义Passarino-Veltman约化方法和外尔费米子相关的理论问题。
报告摘要：
Spatial dimensionality of systems and energy dispersion of carriers play a central role in determining most kinds of physical properties. In this talk, we report the effects of spatial dimensionality and energy dispersion on the longitudinal optical conductivities (LOCs) in tilted Dirac materials. Both the LOCs of tilted Dirac cone in arbitrary spatial dimension and the relation between LOCs and joint density of state are analytically obtained. The dimensional dependence of LOCs on the frequency and chemical potential are presented. The characteristic features of LOCs can be taken as signatures of Lifshitz transition therein. The results are expected to be qualitatively valid for a great number of interesting tilted Dirac materials due to the underlying similarities in tilted Dirac bands.

报告题目：Understanding light-induced efficiency enhancement in hybrid-perovskite solar cells

报告人简介：张燮，中国工程物理研究院北京计算科学研究中心特聘研究员，2019年国家海外高层次青年人才计划入选者。2015年取得德国马普钢铁研究所和鲁尔波鸿大学博士学位（导师：Jörg Neugebauer教授）。曾先后在德国马普钢铁研究所和美国加州大学圣芭芭拉分校材料系（导师：Chris G. Van de Walle院士）从事博士后研究，并于2020年11月全职回国。专注于先进结构与能源材料中缺陷与相变的第一性原理研究。近年来在Nat. Mater., Nat. Commun., Sci. Adv., Phys. Rev. Lett., Adv. Energy Mater.等国际一流期刊发表研究论文数十篇。2018年获得加州大学圣芭芭拉分校固态发光与能源电子中心杰出研究成就奖。2019年获美国能源部国家能源研究科学计算中心所颁发的高影响力科学计算青年成就奖。
报告摘要：
It was observed in recent experiments that light exposure could induce pronounced lattice expansion of hybrid perovskites, which in turn enhances the power conversion efficiency of perovskite solar cells by a few per cent. However, the mechanism behind the efficiency enhancement is still unclear. Employing our recently developed methodology for computing defect-assisted nonradiative recombination rates to hybrid perovskite FAPbI3, we show that 1% lattice expansion could decrease the nonradiative capture coefficient by one order of magnitude, drastically extending the carrier lifetime. More interestingly, the decrease is actually not caused by changes in the band gap or defect transition level a result of lattice expansion, but stems from enhanced defect relaxations in the expanded lattice. Our insights not only rationalize the puzzling experimental observation, but also offer a widely applicable pathway to tune nonradiative recombination through light-matter coupling.

报告题目：多尺度模拟方法探究Pt-Ni合金催化剂构效关系

报告人简介：
李佳，清华大学深圳国际研究生院副教授，博士毕业于清华大学大学，博士后工作于德国德国马普学会Fritz-Haber研究所大学，现为清华大学深圳国际研究生院材料研究院副教授、博士生导师。他长期从事计算材料学研究，在低维材料模拟与器件设计领域发表了110多篇论文；曾荣获2019年获得中国材料研究学会计算材料学分会的“计算材料学青年奖”。目前担任中国材料研究学会计算材料学委员会委员。
报告摘要：
在质子交换膜燃料电池(PEMFC)中，正极处相对缓慢的氧还原反应(ORR)限制了燃料电池的整体性能。因此ORR催化剂材料在提升燃料电池性能上起到重要作用，Pt-Ni合金催化剂体系是其中一种优秀的材料体系。Pt-Ni合金催化剂体系有着多样的纳米结构，且在工作环境下也会发生结构变化，实验表征方法很难得到这些纳米催化剂的原子级别结构，因此目前对其结构与整体催化活性之间的关系还没有明确的解释。为了解决上述问题，我们使用动力学蒙特卡洛方法(KMC)和密度泛函理论计算(DFT)的多尺度模拟方法，开展对Pt-Ni合金催化剂的微观结构与催化剂整体催化活性之间的关系的研究。我们使用了图论方法，用图来表示合金纳米颗粒的结构，并使用图核函数的方法计算得到结构之间的相似程度，从而筛选出相似程度较低的初始结构空间，之后在该结构空间中使用主动学习的方法筛选出有效的训练集结构进行Pt-Ni全成分范围的机器学习力场拟合，其中采用的机器学习模型为神经网络模型。模型对于测试集结构的能量预测精度与DFT计算结果相比，误差在0.01~0.02eV/atom，并且与随机产生的结构空间训练得到的模型相比，误差降低了30%。训练得到的力场被用于提供KMC过程中的原子间相互作用，这里我们分别研究了成分为Pt3Ni2、Pt1Ni1和Pt2Ni3的八面体纳米颗粒在工作环境下表面脱Ni现象导致的结构演变过程。模拟结果给出了纳米颗粒结构变化的结构轨迹，不同成分颗粒之间存在明显的区别，且脱Ni过程和最后的结构、成分都能与实验结果符合。同时DFT计算被用于获得表面不同配位环境的Pt催化位点的OH吸附能数据，以拟合吸附位点配位环境与OH吸附能的相关关系。最后，我们希望能够综合KMC方法得到的催化剂微观结构和基于DFT计算数据拟合的OH吸附能结构信息描述符，通过统计学方法，评估Pt-Ni催化剂纳米结构的整体催化活性。

报告题目：First-principles study of Dzyaloshinskii-Moriya interaction and topological magnetism in 2D magnets

报告人简介：

杨洪新，中国科学院宁波材料技术与工程研究所研究员，量子功能材料团队负责人。获国家海外高层次引进人才计划支持，于17年加入宁波材料所。杨洪新研究员一直致力于自旋电子学理论计算研究，主要研究磁随机存储器以及磁斯格明子应用中涉及到的基本物理学现象。在自旋电子学领域主要贡献有：（1）发展了基于第一原理的投影轨道特征谱分析垂直磁各向异性，原子层分辨和轨道杂化分辨计算分析垂直磁各向异性的方法，阐明了铁磁材料/金属氧化物界面的巨大垂直磁各向异性的物理机制，预言了在MgO基磁隧道结可以同时实现巨大TMR和PMA，并获实验验证，解决了STT-MRAM的一个关键问题。（2）发展了基于DFT计算界面Dzyaloshinskii-Moriya interaction (IDMI)的方法，从而在第一性原理层面阐明了铁磁金属/重金属界面DMI的物理机制；预言多种界面DMI材料并提出多种调控方法，被大量实验所验证，获得同行的认可，为基于手性磁畴及Skyrmion的磁存储应用提供重要理论指导。已发表论文70余篇。Nature等杂志审稿人。在APS March Meeting等学术会议作邀请报告30余次。主持多项国家及省部级项目。

报告摘要：
The Dzyaloshinskii-Moriya interaction (DMI) has attracted significant interest because it plays a tremendous role for fast domain wall motion and allows the creation of topological quasi-particles, e.g. magnetic skyrmions, chiral domain walls, and bimerons, etc., which are very promising for ultra-dense/ultra-low energy consumption information storage and logic devices.
Spin-orbit coupling and absence of inversion symmetry are the two ingredients for the existence of DMI. Most state-of-the-art experiments and devices of today use the interface between two crystals to break the inversion symmetry and create DMIs, such as DMI in heterostructures between ferromagnetic metals and heavy metals or heterostructures between ferromagnetic metals and graphene. In those heterostructures, it is known that intricate adjustment of the layer thicknesses, stacking sequences, or chemical composition, etc., are often necessary to control the strength and/or chirality of DMI [Nat. Mater. 16, 898 (2017); Sci. Rep. 8, 12356 (2018)]. More interestingly, how to induce DMI in 2D magnets actually can even scale down the spintronics devices using topological spin textures. Basically, one can use Janus magnets, or intrinsic p-4m2 symmetry protected 2D magnets, etc.
At the same time, it is a long-desired expectation to realize topological magnetism and its electric control for applications in information storage and logic technologies. Here, we propose that both can be achieved in two-dimensional (2D) magnetoelectric multiferroics simultaneously. We demonstrate that the obtained significant DMI is switchable and can promote tunable sub-10 nm skyrmions in 2D multiferroics with perpendicular magnetic anisotropy such as in a CrN or Co(MoTe2)2 monolayer.
Based on the electrical switchable DMI [5], we designed one single nanotrack with complete logic functionality, which can be programmed via voltage-switched DMI. By reconstructing DMI chirality barriers, we successfully realize the annihilation, fusion and pinning of skyrmions, and then the complete Boolean family including AND, OR, NOT, NAND, NOR, XOR, and XNOR are implemented in one single nanotrack. We believe that this work represents an important step towards the development of all-electric manipulation of skyrmion-based logic and memory, paving the way for future skyrmionic in-memory computing.

报告题目： A micromagnetic simulation package based on COMSOL Multiphysics

报告人简介：肖江，复旦大学物理系 教授、博士生导师。研究凝聚态理论物理、自旋电子学、磁学。主要研究各种磁性材料和结构中的自旋输运行为和特性，如自旋转移力矩、磁矩动力学、自旋泵浦、自旋塞贝克效应以及自旋相关的热电噪音等物理现象。为今后几十年的信息技术进步奠定必要的理论基础。

https://phys.fudan.edu.cn/f7/5a/c7605a63322/page.htm
报告摘要：
Micromagnetic simulation is a numerical method widely used in studying magnetization dynamics and spin wave by treating the magnetization as a semi-classical quantity with coarse grain average in space. We developed a micromagnetic simulation package based on the widely used simulation app COMSOL Multiphysics. This new micromagnetic simulation tool can efficiently compute magnetization dynamics in several different types scenarios, including i) the static magnetization profile stabilization such as magnetic domain walls, magnetic skyrmions , ii) computing in time domain for the spin wave behavior excitation and propagation, and the dynamics of magnetic textures such as the magnetic domain wall or skyrmion motion, iii) computing in frequency domain for spin wave dispersion in trivial or non-trivial magnetic textures, and more importantly, iv) coupled to other physical fields such as the electromagnetic fields, thermal fields, mechanical fields that have already been embedded in COMSOL.

报告题目：Optical control of multi-stage phase transitions in condensed matters

报告人简介：Dr. Sheng Meng is a professor and head of the Surface Quantum Dynamics group at Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences since 2009. He obtained his Bachelor degree in physics from University of Science and Technology of China (USTC) in 2000, and Ph.D. degree in condensed matter physics from Institute of Physics, Chinese Academy of Sciences and applied physics from Chalmers University of Technology, Sweden in 2004. During 2005-2009, he worked at Harvard University’s Department of Physics first as a post-doctoral researcher then a research associate. Dr. Meng’s research interests focus on quantum electron dynamics in condensed matter; design of quantum materials; and electronic/quantum origin of wetting. He has published ~200 technical papers in peer-reviewed journals, and has received 10000+ citations with a H-index 55.
报告摘要：
The temporal characters of laser-driven phase transitions have been investigated using time-dependent first principles simulations in prototype materials including MoTe2, VO2 and liquid water. The process is found to be induced by fundamental electron-phonon interactions, with an unexpected phonon excitation and coupling pathway closely related to the nonequilibrium relaxation of photoexcited electrons. The order-to-order phase transformation is dissected into three substages, involving energy and momentum scattering processes from optical to acoustic phonon modes in sub-picosecond timescale. Intermediate states along the nonadiabatic transition pathway is also identified. These results have profound implications on nonequilibrium phase engineering.

报告题目：Magnetic anisotropy dominated spiral to antiferromagnetic transition from bulk to monolayer NiI2

报告人简介：季威，中国人民大学物理学系教授。2008年从中国科学院物理研究所获得博士学位，随后在加拿大McGill大学从事博士后研究，2010年进入中国人民大学工作。研究兴趣主要为发展和应用独特的第一性原理计算方法，与实验紧密结合，模拟和预测低维量子系统和信息材料与器件的界面前沿问题。研究成果被选为2011年国际邮票素材、入选2013中国科学十大进展、2014年和2015年中国百篇最具影响国际学术论文。2014-2016年获得三个国家级青年人才计划或创新项目支持，2019年入选中科院青促会首批特邀会员，2021年入选国家高层次人次奖励计划。目前担任中国材料研究学会计算材料学委员会委员；ACS Applied Electronic Materials副主编，Science Bulletin、Chinese Physics B、《物理学报》、2D Materials和Frontiers of Physics编委。报告摘要：
Mono- and few-layer NiI2 were recently evidenced to be two-dimensional type-II multiferroic materials. Such assessment is, however, based on an assumption that the spiral magnetic configuration of NiI2, experimentally found in its bulk counterpart, persists to the monolayer (1L) limit and it does not significantly contribute SHG signal. Here, we found that such hasty assumption is flawed at the monolayer limit where freestanding 1L NiI2 prefers to striped antiferromagnetism using density-functional-theory calculations. This configuration offers an intralayer antiferroelectricity. Thus, the NiI2 monolayer is, indeed, a type-I multiferroic material with both antiferromagnetism and antiferroelectricity. Such a magnetic groundstate variation from bulk to 1L NiI2 originates from the competition between in-plane single ion anisotropy of Ni atoms and out-of-plane contribution of interfacial I atoms to magnetic anisotropic energy (MAE). These theoretical results not only unveil the magnetic groundstate of 1L NiI2, but also enlighten us the role of layer-stacking induced change of magnetic anisotropy in thickness-dependent magnetic transitions of two-dimensional magnets.

报告题目：Ultrafast Charge Transfer Coupled to Quantum Proton Motion at Molecule/Metal Oxide Interface

报告人简介：
Jin Zhao received her B.S. degree from the University of Science and Technology of China (USTC) in physics in 1998. After that, she joined the research group of Prof. Hrvoje Petek at the University of Pittsburgh in 2004. In March 2010, she returned to USTC as a Professor. The focus of her research is ab initio investigations on the electronic structure and excited carrier dynamics in condensed matter systems. Her group has developed ab initio nonadiabatic molecular dynamics code Hefei-NAMD (http://staff.ustc.edu.cn/~zhaojin/code.html).
报告摘要：
Understanding how the nuclear quantum effects (NQEs) in the hydrogen bond (H-bond) network influence the photoexcited charge transfer at the semiconductor/molecule interface is a challenging problem. By combining two kinds of emerging molecular dynamics methods at the ab initio level - the path-integral based molecular dynamics and time-dependent nonadiabatic molecular dynamics, and choosing CH3OH/TiO2 as a prototypical system to study, we find that the quantum proton motion in the H-bond network is strongly coupled with the ultrafast photoexcited charge dynamics at the interface. The hole trapping ability of the adsorbed CH3OH molecule is notably enhanced by the NQEs, and thus, it behaves as a hole scavenger on TiO2. The critical role of the H-bond network is confirmed by in-situ scanning tunneling microscope measurements with UV light illumination. It is concluded the quantum proton motion in the H-bond network plays a critical role in influencing the energy conversion efficiency based on photoexcitation.

报告题目：新型二维磁性体系理论设计及其功能异质结研究

报告人简介：侯玉升，中山大学“百人计划”副教授，2016年6月复旦大学物理系博士毕业， 2016年9月至2020年10月在美国加利福尼亚大学尔湾分校从事博士后研究， 2020年11月作为百人计划引进人才加入中山大学物理学院，是广东省磁电物性分析与器件重点实验室和中山大学物理学院中子科学与技术中心固定研究人员。主持国家自然科学基金青年科学基金项目和广东省自然科学基金面上项目，参与国家自然科学基金重大研究计划。主要研究方向是计算凝聚态物理，近年的工作涉及磁性拓扑材料和二维磁性研究等。相关成果发表在Nature, Science Advances, Nano Letters, Nature Communications, npj Computational Materials，Advanced Functional Materials等国际一流学术期刊上。
报告摘要：
自从2017年在范德瓦尔斯材料Cr2Ge2Te6和CrI3中发现二维磁性以来，二维磁性体系及其异质结在自旋电子、能谷电子和光电子器件中的应用前景引起了人们的巨大兴趣。在本报告中，我将介绍我们在新型二维磁性体系理论设计及其功能异质结方面的一系列研究。我们发现铁磁体CrI3单层能磁化三维拓扑绝缘体表面态，提出在CrI3/Bi2Se3/CrI3异质结中实现较高温度的量子反常霍尔效应。我们设计了范德瓦尔斯层状反铁磁体Mn2Bi2Se5，提出了在实验上容易实现轴子绝缘体态的MnBi2Se4/Bi2Se3/Mn2Bi2Se5异质结。利用二维范德瓦尔斯雅努斯材料不同面阴离子高度可调性，我们设计了高居里温度的、外层阴离子具有目前报道的最大自旋极化的的铁磁半导体铬基硫卤化物CrSX (X=Cl、Br、I)。我们发现大带隙的量子反常霍尔效应和较大的能谷劈裂可以分别在范德维尔斯异质结CrSBr/Bi2Se3/CrSBr和MoTe2/CrSBr中实现。此外，CrTeX (X=Cl、Br、I)则可以实现磁斯格明子。最后，我们在Co2CF2中预言了室温下的铁磁铁电态，在Co2CF2/MoN2异质结中提出了电控磁序相变。

报告题目：Anomalous Hall Effect in Non-collinear Anti-Ferromagnetic L12-type Mn3Ir

报告人简介：夏钶，北京计算科学研究中心Chair Professor,国家杰出青年科学基金获得者。主要从事量子输运理论、自旋电子学仿脑计算、电子结构计算方法发展等方向的研究。夏钶教授自行发展了基于第一原理计算纳米体系电子输运的理论方法，可以同时处理真实材料在实验条件下的电子及自旋输运问题，并将此方法成功地用于研究：a)磁性-非磁性界面，b)自旋极化电流对磁矩的转矩(spin torque)；c)铁磁/超导体界面的Andreev反射；d)反铁磁材料。在SCI收录的杂志上发表文章80余篇(含Nature Nano.PRL等10余篇)，在国际会议做邀请报告数十次。
http://www.csust.edu.cn/wdxy/info/1225/4622.htm?urltype=tree.TreeTempUrl&wbtreeid=1226
报告摘要：
The anomalous Hall effect is generally treated as a direct response to the injecting charge current with spin-orbit interaction in magnetic materials. Recently, many works on the anomalous Hall effect in non-collinear anti-ferromagnetic materials are reported from both theoretical and experimental groups. And the physical origin of this anomalous Hall effect is mainly attributed to the Berry curvature.
In this work, using a first-principles-based scattering wave function approach, we study the anomalous Hall effect in non-collinear anti-ferromagnetic L12-type Mn3Ir and find that the corresponding anomalous Hall conductivity can be as large as 3.4×〖10〗^4 [Ω∙cm]^(-1) at low temperature, which is two orders of magnitude larger than that from Berry curvature calculations, indicating that the Berry curvature may not enough for this novel anomalous Hall effect.
With a detailed analysis of the anomalous Hall effect therein, we found that the scattering process dominates. We propose that the anomalous Hall current is coming from the combination of the Ir induced conventional/inverse spin Hall effect and the spin reorientation when the corresponding spin current passes through the local magnetic moments of Mn in L12-type Mn3Ir. This indirect anomalous Hall effect should be universal in non-collinear anti-ferromagnetic materials and needed further study in the future.

报告题目：Topological PhotoElectric Effect in Topological Phase Transition

报告人简介：翁红明，中科院物理所 研究员，博士生导师，2017年9月起任理论室副主任。研究拓扑量子态及其材料计算研究，磁光效应，非线性光学效应等第一性原理计算。主要从事计算凝聚态物理方向的研究工作，一方面致力于计算方法和程序的开发，另一方面着重于凝聚态物质中新奇量子现象的计算研究。迄今（2022年2月）共发表SCI论文200余篇，被引用2100次，h-因子57。2018-2021连续四年入选科睿唯安“全球高被引科学家”。

报告题目：面向材料领域的高性能计算

报告人简介：琚生根，四川大学教授。多年来一直从事智能信息处理的研究，具体研究方向包括图像篡改识别认证、数据挖掘、医学信息化工程等。已在权威国际国内学术期刊和国际会议上发表论文50余篇，其中SCI或EI收录12篇；主持或参加多项纵横科研项目。计算机学会会员，ACM会员，四川大学学报（自然科学版）等核心期刊审稿人。主持科研和工程项目5项，作为第一主研参与国家自然科学基金项目3项。有着丰富的科研和工程实践经验。

报告摘要：
在现代科学研究和工程实践中，通常使用数学方程式来表示某些自然科学规律，普通计算已经难以满足愈发复杂的计算公式，利用超级计算机进行科学计算可以极大地提高运算效率。高性能计算机能够达到每秒亿亿次的浮点运算速度，已经成功应用于生物计算与精准医疗、全数字设计与制造、地球科学与环境工程、智慧城市云计算和材料科学与工程等领域，并取得相当成果。本讲座主要阐述高性能计算的概念、应用领域，并总结其材料领域的应用需求、现状与成果。

报告人名单和报告题目、摘要持续更新中，敬请期待！

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编辑：王媛媛

蔻享学术平台，国内领先的一站式科学资源共享平台，依托国内外一流科研院所、高等院校和企业的科研力量，聚焦前沿科学，以优化科研创新环境、传播和服务科学、促进学科交叉融合为宗旨，打造优质学术资源的共享数据平台。

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