Observation of Nearly Quantized Majorana Conductance Plateau in an Iron-based Superconductor

<正>In 1937, Ettore Majorana, an Italian physicist, predicted an elementary particle called the Majorana Fermion, for which the particle is its own anti-particle. The Majorana Fermion in condensed matter physics is also known as the Majorana zero mode. Because Majorana zero modes obey non-Abel statistics, it holds a great promise for the realization of topological quantum computing, which has attracted widespread interest.     

Creating Majorana fermions in topological insulators

<正>Having not been veriied in experiments yet,the concept of Majorana fermions was originally hypothesized in 1937 to describe the spin-1/2 particles that are their own antiparticles,in contrast to Dirac fermions[1],which difer from their antiparticles and cover most of wellknown fermions including quarks,leptons,electrons and their antiparticles.     

Discovery of Majorana Bound State in Fe-based Superconductor

正In 1937, Italian theoretical physicist Ettore Majorana published a paper, in which he made a brilliant discovery by decomposing Dirac equation into the real and imaginary parts. That is the famous equation describing the motion of a Majorana fermion whose antiparticle is itself. Over the past 81 years, the search     

英国知识要素参与分配的实践与思考

从２０世纪初著名的经济学家马歇尔（Ｍａｒｓｈａｌｌ）提出“知识是经济发展的首要引擎”的论断到今天，知识在推动经济增长方面已显示出巨大驱动力。许多有识之士把今天由知识经济引发的变革等同于１８世纪瓦特发明蒸汽机所引发的世界工业革命，其寓意不可不谓深远。知识经济正在快步向我们走来，它所带来的变革将是巨大和深远的。首先知识的创造和开发成为人类创造财富的重要方式；推动世界经济由传统的物质资源驱动向知识资源驱动的转变；极大地压缩了世界经济地理空间，加剧了竞争；影响并改变世界传统资源力量对比。 英国作为老牌资…     

A new twist on graphene: an interview with Pablo Jarillo-Herrero and Allan MacDonald

Graphene is the building block of graphite, made of carbon atoms bonded into sheets of hexagonal rings just a single atom thick. Although such isolated sheets had been predicted for many decades to exist, and had been grown on other surfaces, interest in this material exploded after the discovery in 2004 that single sheets could be made easily and cheaply by separating them mechanically from graphite flakes (a process called exfoliation). Although graphene is often advertised as a ‘wonder material’—electronically conducting, transparent and extremely strong and flexible—much of the interest in it is more fundamental. As a 2D conductor, graphene shows unusual electronic and magnetic properties that enable the study of quantum-mechanical effects of confinement and of correlations between electron motions—some of which might find applications in electronic devices. The excitement of this discovery was reflected in the award of the 2010 Nobel Prize in Physics to two pioneers in the field: Andre Geim and Konstantin Novoselov of the University of Manchester in the UK.This rich behavior is broadened still further when two graphene sheets are brought close enough to interact with one another. In particular, the electronic properties may then depend on the relative orientation of the sheets: how aligned the two ‘honeycomb’ lattices are. Two grids superimposed on one another may create ‘superlattices’: regularities at larger scales than the grid spacing, due to registry (commensurability) between the two at certain angles. This so-called moiré effect is sometimes evident for two closely spaced grid-like fences seen from afar. Experimentally exploring the electronic properties of such ‘twisted bilayer graphene’ requires an ability to precisely control the position and orientation of the two sheets. These phenomena are now recognized as generic to other 2D materials, such as hexagonal sheets of boron nitride. They have revealed a fertile playground for condensed-matter physics. In particular, striking electronic properties appear at certain ‘magic-angle’ twists of the layers.NSR spoke to two of the leading experts in the study of magic-angle twisted bilayer graphene (MATBG): experimentalist Pablo Jarillo-Herrero of the Massachusetts Institute of Technology and theorist Allan MacDonald of the University of Texas at Austin.     

High-Tc superconductor Fe(Se,Te) monolayer: an intrinsic,scalable and electrically tunable Majorana platform

Iron-based superconductors have been identified as a novel platform for realizing Majorana zero modes (MZMs) without heterostructures, due to their intrinsic topological properties and high-T_c superconductivity. In the two-dimensional limit, the FeTe_1−xSe_x monolayer, a topological band inversion has recently been experimentally observed. Here, we propose to create MZMs by applying an in-plane magnetic field to the FeTe_1−xSe_x monolayer and tuning the local chemical potential via electric gating. Owing to the anisotropic magnetic couplings on edges, an in-plane magnetic field drives the system into an intrinsic high-order topological superconductor phase with Majorana corner modes. Furthermore, MZMs can occur at the domain wall of chemical potentials at either one edge or certain type of tri-junction in the two-dimensional bulk. Our study not only reveals the FeTe_1−xSe_x monolayer as a promising Majorana platform with scalability and electrical tunability and within reach of contemporary experimental capability, but also provides a general principle to search for realistic realization of high-order topological superconductivity.     

基于Zigbee的智能停车系统

针对当前城市中普遍存在的停车难及停车场管理不规范的问题,提出了一种基于ZigBee技术的智能停车场管理系统.通过安装在每个车位上方的超声波车位探测器,实时采集停车场的各个车位的车辆信息.连接探测器的节点控制器会按照轮询的方式,对所连接的各个探测器信息进行收集,并按照一定规则将数据压缩编码后反馈给中央控制器,由中央控制器完成数据处理,并将处理后的车位数据发送到停车场各个车位引导屏进行空车位信息的显示,从而实现引导车辆进入空余车位的功能.系统同时将数据传送给计算机,由计算机将数据存放到数据库服务器,用户可通过计算机终端查询停车场的实时车位信息及车场的年、月、日的统计数据.本方法比传统的停车场管理方式更加准确、便捷、高效.     

EAST gets a head start in steady-state tokamak physics

While the International Thermonuclear Experimental Reactor (ITER) project is underway at Cadarache, France, an initiative in building the next-generation tokamak at the CAS Institute of Plasma Physics (ASIPP) in Hefei, capital of east China's Anhui Province, offers crucial expertise.     

高职教育--"灰领人才"的摇篮

随着经济的发展,对复合型人才的需求,“灰领”成为越来越被关注的群体,对于“灰领人才”的培养也就成为一个需要重视的问题,正在不断兴起壮大的高职院校成为了“灰领人才”的摇篮,高职教育正冲破重重阻力,不断地向社会输送大批高技能的实用型人才,同时期待着更多的瞩目与关爱。     

Young CAS biologist gets five-year grant from Howard Hughes Medical Institute

Dr. TANG Chun, an outstanding young biologist from the CAS Wuhan Institute of Physics and Mathematics (WIPM) was announced in January 2012 to have won the first International Early Career Award from Howard Hughes Medical Institute with a five-year grant totaling up to 650,000 US dollars. Dr. Tang is an expert in using novel nuclear magnetic resonance methods to study the behavior and function of proteins,