Study on phase transformation of Chinese topology is also very strong – Zhejiang channel — people.c

The study of topological phase change in China is also very strong – Zhejiang channel people’s original title: topological phase transition research, China is also a strong bismuth telluride stone, ordinary people classify it as "solid", but its accurate classification should be "topological insulator"". "Topology" two words plus one, the existence of the material is greatly enriched. In October 4th, three Americans were awarded the Nobel prize in physics for 2016 years because of the study of topological phase transition. Chinese scientists have also shown great success in this field in recent years. "I read their articles and started the research, and they admired their work very much, and they created the direction of the whole topological state of things." Study on the Erfeimi Physics Institute researcher Weng Hung Ming told Technology Daily reporter, said. Two dimensional and three-dimensional topological materials, quantum anomalous Holzer effect, Erfeimi sub…… In recent years, some well-known physics breakthroughs of Chinese scientists are related to "topological phase transition". Topological materials, Weng Hongming says, are not only in laboratories, but also in nature. The American scientist, who was awarded the Nobel Prize, did a very open job, and later researchers have expanded very far, and we have taken a step further into the understanding of nature. Chinese scientists are currently the largest in the field of research, and are leading the world in the direction of outer half metal, Dirac and semi metals. Xue Qikun, a professor at Tsinghua University, also said that after the foundation work of the three Nobel laureates, scientists in this field have been able to develop three-dimensional topological insulators since 2005, including the famous Chinese physicist Zhang Shousheng. Chinese scientists have also made a lot of important work. In terms of the synthesis of topological materials, characterization of basic properties and the discovery of physical effects, Chinese physicists are already in the first echelon of the world. A material can exhibit different phases, such as pure carbon, either graphite or diamond. Physicist Landau proposed that matter changes from one phase to another, and the nature is the transformation of high symmetry state and low symmetry state. In any direction, the water with symmetrical molecular structure turns into a symmetrical ice in a specific direction, in essence, its symmetry drops or breaks. But Landau’s theory doesn’t make sense in a particular case – some insulators turn into conductors, which certainly change, but symmetry doesn’t change. It was later discovered that the phase transition was due to the change in the topological properties of the material. Roughly speaking, it is a geometric structure (without holes) in the material that turns into a bracelet (1 holes), and turns into a frame (2 holes), which changes the movement environment of the electron. The theory of geometric topology, which was introduced to the study of phase transition, would like to thank three American scientists who had just won the Nobel prize. Insulators, conductors, superconductors…… These substances can change, but also is a paradox, no evil. For example, topological insulators do not conduct electricity inside, but their surfaces are electrically conductive, and the energy consumption is very low; some materials are ordinary metals, and the inner ones are superconductors. So people expect these strange materials to be used in future circuits.

拓扑相变研究中国也很强–浙江频道–人民网 原标题:拓扑相变研究中国也很强 一块碲化铋石头,普通人把它归类为“固体”,但它的准确分类应该是“拓扑绝缘体”。“拓扑”二字一加,物质的存在方式极大丰富。10月4日,三位美国人因为“拓扑相变”研究被授予2016年度诺贝尔物理学奖。而中国科学家近几年也在这一领域大放异彩。 “我读着他们的文章开始了研究,对他们的工作非常敬佩,他们开创了整个拓扑物态的方向。”研究外尔费米子的中科院物理所翁红明研究员接受科技日报记者采访时说。二维和三维拓扑材料、量子反常霍尔效应、外尔费米子……近年来中国科学家的一些知名的物理突破,都与“拓扑相变”相关。 翁红明说,拓扑材料不光是在实验室里,在自然界也广泛存在。此次被授予诺奖的美国科学家,做的是极具开放性的工作,后来的研究者已经拓展了非常远,让我们对自然界的认知又进了一步。中国科学家目前在这一领域的研究实力,是全球数一数二的,在外尔半金属、狄拉克半金属等方向上领先世界。 清华大学教授薛其坤也表示,三位诺奖得主的奠基性理论工作之后,这一领域因2005年包括华裔著名物理学家张首晟在内的科学家发现三维拓扑绝缘体材料得以发展。中国科学家也做出很多重要工作,在拓扑材料的合成、基本性质表征以及物理效应的发现等方面,中国物理学家已经处于国际第一梯队。 一种物质可以呈现出不同的相,比如纯净的碳可以是石墨,也可以是钻石。物理学家朗道提出,物质从一种相变成另一种相,本质是高对称状态与低对称状态的转变。从哪一个方向看分子结构都对称的水,变成了特定方向看才对称的冰,实质是它的对称性下降了,或者说“破缺”了。 但是,朗道的理论在一种特殊情况下讲不通――有些绝缘体变成导体,相肯定变了,但对称性却没变化。后来才发现,这种相变,是因为物质的“拓扑性质”变了。大概说来,就是物质里某种像饭碗一样的几何结构(没有洞)变成了手镯(1个洞),又变成了眼镜框(2个洞),改变了电子的运动环境。本来是几何学的拓扑理论,引入到物质相变的研究,要感谢刚拿到诺奖的三位美国科学家。 绝缘体、导体、超导体……这些物质相可以变来变去,还可以亦正亦邪,正邪不分。比如说,拓扑绝缘体内部不导电,但是它的表面却导电,而且能耗极低;还有些材料,表面是普通金属,内部却是超导体。所以大家期待这些奇怪的材料能用于未来的电路。相关的主题文章: