报告介绍 报告摘要： The performance of graphene-based bulk materials is dependent not only on the structure and properties of individual sheets, but also on the intersheet interactions and their hierarchical texture or its supramolecular structure. Our group has been studying the supramolecular chemistry of chemically converted graphene and how non-covalent interactions can be utilized to create carbon-based...

报告介绍 报告摘要： Thegenerationand study of translationally cold (T<< 1K) molecules and molecular ions represents one of the most recent and exciting new developments in physical chemistry. Molecular ions can be cooled and Coulomb crystallized by exchanging kinetic energy with laser cooled atomic ions by means of the Coulomb interaction (“sympathetic cooling”) thus forming bi-component or...

报告介绍 Abstract：　　100 years into the discovery of superconductivity, only a handful of materials demonstrate Tc's above the empirical electron-phonon McMillan limit - the H3S under pressure, the iron-based single crystal superconductor, the mono-layer FeSe/STO and the high Tc cuprate superconductors. While ultrahigh vacuum (FeSe/STO) and high pressure (H3S) impose intrinsic limitations for a comprehensi...

报告介绍 Abstract： As established in the very early work of Edwin Hall, ferromagnetic conductors have an anomalous Hall conductivity contribution that cannot be attributed to Lorentz forces and therefore survives in the absence of a magnetic field. These anomalous Hall conductivities are normally assumed to be proportional to magnetization. We use symmetry arguments and first-principles electronic structure...

报告介绍 报告摘要：　　WTe2因其强自旋轨道耦合、半金属输运、迥异的对称性、二维受限和高迁移率等特性，成为一种物理内容十分丰富的新型量子材料。我们就此材料开展了三项工作：1）利用迁移率谱的方法，解析了电子空穴型载流子精致平衡的输运特性，并发现线性磁电阻的成分。2）利用高分辨ARPES解析获得清晰的费米面结构，发现其具有圆二色性，并提出了一种各向异性的磁电阻机制。3）采用高压诱导了WTe2系统的超导特征，描绘一幅拱型压力-临...

报告介绍 报告摘要： We study the strong coupling between photons and atoms that can be achieved in an optical nanofiber geometry when the interaction is dispersive. While the Purcell enhancement factor for spontaneous emission into the guided mode does not reach the strong-coupling regime for individual atoms, one can obtain high cooperativity for ensembles of a few thousand atoms due to the tight confinemen...

报告介绍

报告介绍 Abstract: 　　Topological insulators (TIs) are characterized by an unusual electronic structure exhibiting both insulating bulk and robust metallic surface states (SSs). This unique electronic structure combining external light excitation leads to TIs a great promise for opto-spintronics and ultrafast spintronics applications. Therefore, understanding the charge and spin dynamics in TIs becomes quit...

报告介绍 Abstract： 　　Electrochemical reactions, e.g. oxygen reduction (ORR), hydrogen evolution (HER) and oxygen evolution reaction (OER), are key to energy conversion and storage. For example, ORR is a determining step for fuel cells; HER and OER are for water splitting; Combination of ORR and OER can form a metal-air battery. Up to now, platinum (Pt) exhibits the best performance, and Pt/C is the commer...

报告介绍 Abstract： Synthesis of interfaced nanoparticle dimers made of asymmetric compositions (i.e., interfaced heterodimers) is challenging because it is difficult to manipulate the nanoparticles’ surface properties to control the assembly and/or growth of different nanoparticles. In this presentation, the general principle will be first introduced for the formation of interfaced heterogeneous ...

报告介绍 Abstract：Electron microscopy is a very standard powerful technique for the study of atomic structure of materials. In this talk, I will discuss two recent developments in this field: quantitative high angle annular dark field electron microscopy (HAADF-STEM) and electron vortex beam. We will use the quantitative HAADF-STEM imaging of nanoclusters to show that not only we can determin...

报告介绍 报告摘要： The boom of graphene research has stimulated great interest in two-dimensional form by other elements, either single element or composite materials. Among these 2D materials special interest have been paid on those formed by carbon neighbors, such as group IV elements (Si, Ge, Sn), and its neighboring element, boron and nitrogen. 2D materials formed by carbon neighbors may possess intrigu...

报告介绍 Abstract:　　The past few years witnessed the explosion of research on photovoltaic cells based on the hybrid lead halide perovskites, in particular CH3NH3PbI3. Within a short period of 5 years, the efficiency of these cells has increased from 3.8% to over 20%. Despite the tremendous progress in device performance, much less is known about the underlying mechanism except that the carrier lifetime an...

报告介绍 报告人简介：1981–1988年在兰州大学化学系有机化学专业学习，分获理学学士学位和理学硕士学位。1988–1993年在西南师范大学化学系从事有机化学教学和科研工作，历任助教和副教授。1993–1996年在中国科学院化学研究所学习，获理学博士学位。1996–2000年在中国科学院成都有机化学研究所从事不对称催化反应研究，历任副研究员和研究员。1998–1999年在美国Colorado State University化学系做博士后研究。20...

报告介绍 Abstract: 　　Bacteria living in confined geometries are commonly found in clinical and natural environments. We are particularly interested in the behavior of bacteria confined in thin liquid films, because thin-film environment is relevant to biofilm formation, swarming, and bacterial colonization in interstitial space between tissues. In thin-film environment, the interactions between c...

报告介绍 Abstract:　　Ultrathin films of transition metal dichalcogenides (TMDs) are of great current research interests for their promises in two-dimensional electronics, optoelectronics, spin and valley electronics. In this talk, I shall describe our latest efforts of molecular-beam epitaxy (MBE) of ultrathin layers of MoSe2 and WSe2. By scanning tunneling microscopy and spectroscopy (STM/S), we reveal bot...