Discovery of "super elastic" electrons in graphene recently, andreheim team, who won the Nobel Prize in physics for the successful preparation of monoatomic layer graphene, observed the movement behavior and conductive mechanism of electrons in graphene contrary to common sense, and expounded a new understanding of the physical properties of this conductive material
graphene has higher conductivity than copper, partly because of its unique two-dimensional structure. In most metals, the conductivity is limited by crystal defects. When electrons pass through the material, they will scatter as frequently as billiards. In the nano electron transport theory, the Randall butik conductivity formula describes the scattering characteristics of such elastic electrons, which shows that normal conductive materials face severe restrictions to improve conductivity
however, the latest results of the research team at the University of Manchester in the UK show that this basic limitation may be broken in graphene materials. Experiments conducted at the national graphene Institute in the UK provide a basic understanding of the special behavior of electron flow in graphene. Experiments by three different teams, including the Manchester University experimental machine (UTM) through conditioning at different speed levels, showed that at some temperatures, electrons collided with each other and began to flow like viscous liquids frequently
Heim said: "textbooks say that additional obstacles always produce additional resistance, but in this case, as the temperature rises, the obstacles caused by electron scattering actually reduce the resistance. The year 2012 is the golden age of the North American plastic machinery market, and the speed of electrons flowing like liquids is faster than free propagation in vacuum. This unique phenomenon is completely counter intuitive!"
usually, scattering events will reduce the conductivity of materials, but this observation overturns common sense - some electrons stick near the edge of graphene crystal, and their kinetic energy dissipation is the highest and their movement is the slowest; At the same time, they protect adjacent electrons from colliding with these areas, resulting in other electrons becoming extremely elastic, flowing smoothly and having a sharp increase in conductivity due to the help of these "friends"
more importantly, by studying how the resistance changes with temperature, scientists have found a new physical quantity - viscous conductivity. Repeated testing and even qualitative research on it are very helpful to guide the design of nano electronic circuits in the future and to have an in-depth understanding of graphene materials
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