報告人：趙新兵，浙江大學
時間：4月13日（周五）9:30
單位：中科院物理所
地點：M樓236報告廳
自1821年T. J. Seebeck發現材料的熱電效應以來，上世紀中葉窄禁帶半導體熱電材料的研究、開發與應用是熱電材料發展歷史上最重要的一個裡程碑。回顧這段歷史並結合一些統計數據分析，我們發現窄禁帶半導體熱電材料的發展源於一個新理論體系的建立與發展，需要對新材料的開拓性深入研究和緊密結合應用的持續努力。以此為啟示，報告就具有研究價值和潛在突破可能的新型熱電材料提出了一些猜想，就一些在熱電材料研究中值得關注的界面影響、成分分布、測量誤差等技術問題進行探討。報告最後結合目前熱電材料領域的「五個90%」現狀，提出未來熱電材料的研究需要在應用導向方面加以更大關注、付出更大努力，並就制約企業提升技術水平的關鍵難題和開拓具有高附加值、高顯示度的新應用領域進行討論。
報告人：陸亞林, 中國科學技術大學
時間：4月12日（周四）16:00
單位：清華大學物理系
地點：理科樓鄭裕彤講堂
新型量子功能材料的一些主要物性與電子及量子態的集體行為（準粒子）密切相關，而這些準粒子行為或多或少與長波長、低能量光子（位於遠紅外到太赫茲頻譜）密切關聯。因而發展新型長波光源技術，實現高空間/高能量解析度、超快的先進長波高通量測量技術，發現新型量子功能材料體系等等就成為關鍵。本報告將簡單介紹我們團隊近年來在這幾個方向的進展：發明緊湊型太赫茲FEL，建設多長條件下高通量材料功能測量，發明參量複合層狀氧化物量子功能材料體系(多鐵性、交換偏置、鐵磁絕緣性)等等。最後簡單介紹目前合肥同步輻射光源的運行和開放服務情況。
報告人： Qiangfei Xia，University of Massachusetts Amherst
時間：4月10日（周二）15:00
單位：北京師範大學物理系
地點：物理樓105
Developing electronics beyond Moore’s Law requires revolutionary vision in novel devices, disruptive technologies, new materials and alternative computer architecture. Memristor (resistance switch) is an emerging nanoelectronic device that uses resistance states to represent digital or analog information. In this talk, I will first describe our recent efforts in developing high performance HfO2 and SiO2 based memristive devices and arrays, including 2 nm scaling and 8 layer stacking. I will then showcase the integration of large memristor arrays (128x64) as multilayer neural networks with applications in analog signal/image processing and machine learning. After a brief introduction of our synaptic and neural emulators with memristors, I』ll finally discuss other applications of memristors such as radiofrequency switches and true random number generators.
4Brunnian neutron cluster
報告人：Johannes Kirscher，The City College of New York
時間：4月11日（周三）10:00
單位：中科院理論物理所
地點：理論物理所322報告廳
Nuclei, composed entirely of neutrons, are an unsolved problem for theory and experiment. I will present a conjecture about the existence of such a bound, pure neutron core whose characteristic is the absence of any bound substructure -- removal of an arbitrary number of neutrons from this core leads to the disintegration of the object in single, free neutrons. As such they present a generalization of the so-called Borromean structure as an emergent property of the nuclear interaction in helium-6. The conjecture is motivated, in part, by QCD simulations which find a bound di-neutron if the quark masses are detuned to larger-than-physical values. I will thus present the implications from the mechanism responsible for the multi-neutron bound state for the search for these objects in QCD simulations.報告人：Hugues Chaté，CEA-Saclay, France and Beijing CSRC
時間：4月11日（周三）10:00
單位：北京師範大學物理系
地點：物理樓106
I will introduce the new emerging field of active matter that deals with the collective properties of self-propelled particles, and then focus on the 'dry' case where the fluid in which the particles move can be neglected. I will present their current knowledge and some recent advances, and argue that statistical physics and nonlinear dynamics tools are necessary for a theoretical understanding of active matter, even in this case.
報告人：Matthew Turner，Warwick univ.
時間：4月11日（周三）14:30
單位：北京師範大學物理系
地點：物理樓106
Here we study behaviour that seeks to maximise the space of accessible (visual) environments out to some time horizon. We apply this principle to individuals that can turn and vary their speed. By exhaustive enumeration of states we show that such 「future state maximization」 (FSM) gives rise to a cohesive swarm that is remarkably similar to those seen in animal systems. We then study two classes of heuristics that mimic computationally intensive FSM. We show that iterative application of these heuristics as the model for the behaviour of 「others」 when determining the dynamics of 「self」under FSM can lead to closure of the problem. Thus, a real-time heuristic approximating FSM is evolutionarily accessible and appears to be in close agreement with data.
報告人：Wenbin Yan，Tsinghua University
時間：4月11日（周三）14:30
單位：中科院理論物理所
地點：Conference Room 6420
The Coulomb branch indices of Argyres-Douglas theories on L(k,1)×S1 are recently identified with matrix elements of modular transforms of certain 2d vertex operator algebras in a particular limit. In this talk I will present a one parameter generalization of the modular transformation matrices of (2N+3,2) minimal models in order to compute the full Coulomb branch index of (A1,A2N) Argyres-Douglas theories on the same space. Morever, M-theory construction of these theories suggests direct connection to the refined Chern-Simons theory. The connection is made precise by showing how the modular transformation matrices of refined Chern-Simons theory are related to the proposed generalized ones for minimal models and the identification of Coulomb branch indices with the partition function of the refined Chern-Simons theory.
報告人：馬銳，耶魯大學
時間：4月11日（周三）16:00
單位：中科院理論物理所
地點：ITP New Building 6420
In this talk, I will present our recent simulations on the self-organization rigid actin filaments in the presence of elastic crosslinkers in conditions relevant for endocytosis. Our simulations demonstrated that these nanometer-scale actin structures can store a large amount of elastic energy within the crosslinkers. This conversion of binding energy into elastic energy is the consequence of geometric constraints created by the helical pitch of the actin filaments, which results in frustrated configurations of crosslinkers attached to filaments. We propose that this stored elastic energy can be used at a later time in the endocytic process.
報告人：楊浩，南京航空航天大學
時間：4月12日（周四）14:00
單位：中科院物理所
地點： M238會議室
Self-assembly has been approved to be a useful method to fabricate oxide thin films with a rich variety of periodic nanoscale patterns. Recent efforts have been focused on how to make the self-assembly controllable. In a film-on-substrate geometry, epitaxial composite films can be divided into two forms: horizontal and vertical. Success of the investigation critically replies on obtain and manipulation of these two architectures. In the present work, horizontally and vertically aligned nanostructures have been obtained in (YBa2Cu3O7-δ)0.5:(BaZrO3)0.5 and (BiFeO3)0.5:(Sm2O3)0.5 thin films respectively. And the manipulation between the vertical and horizontal architectures has been realized in (YBa2Cu3O7-δ)1-x:(BaZrO3)x systems by simply changing the composition of BaZrO3, which resulted from interplay between surface effect and bulk phase separation. The nanostructures dependent lattice constants, strain state, and electrical properties have also been investigated. More details will be presented in the talk.
報告人：Xiangxiang Xue，NAOC
時間：4月12日（周四）16:00
單位：北京大學科維理天文與天體物理研究中心
地點： KIAA-PKU Auditorium
The stellar halo of the Milky Way comprises only a small fraction of all stars in our Galaxy, but these stars are high diagnostic value for probing the Milky Way’s dark matter halo and formation history. Stars extending to ~100 kpc make for an excellent dynamical probe of the halo mass profile, and the long dynamical periods at such large radii (~1 Gyr) mean that the dynamical formation imprint is still very apparent, e.g. in so-called sub-structures. However, Our knowledge of the halo is fragmentary, at least partly because of the paucity of halo stars, with known 3D positions, radial velocities and abundances. Nowadays, with the development of large-scale sky surveys and space astrometry mission, such as 2MASS, SDSS, PanSTARRS1, LAMOST and Gaia, halo star samples are now of sufficient size and quality to boost the study of the Galactic halo. In this talk, I will show you how to map the Milky Way halo using blue-horizontal branch stars and K giants drown from SDSS/SEGUE/LAMOST survey, such as the mass distribution of the dark matter halo, the shape and radial density profile, the metallicity distribution, and substructures of the stellar halo.
報告人：祝世寧，南京大學
時間：4月12日（周四）18:30
單位：中科院大學
地點： 雁棲湖校區教1-207