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Why do not the cool thin sheets of carbon do not resist for electric streams? Two experiments are bringing us closer to a north-and perhaps for practical rooms-Papaman also for superconductors.
Kin Chung Fong In Massachusetts, he was stunned to be another physicist at the Northeast University, Abhishek Banerjee At Harvard University, described him a number in dinner. They were studying various aspects of graphene – carbon sheets were only one atom thick – but both of them estimated how hard it should be for an electric current through the graphine to change.
Previous experiments have shown that very cold stacks of two or three layers of graphene can superconducts, or operate electricity without completely resistance and energy loss, if some sheets are rotated by a special angle . But why this happens was mysterious. Two physicists thought that the estimated property by them in dinner, called the Kinetic Induction, could illuminate the answer.
“Bhavna was when you are hiking wood (through) in the forest, and suddenly you find, okay, wait a minute, I am not the lonely person in this deep forest,” Fong says.
Along with other colleagues, he turned his idea into two experiments. A group measured the kinetic induction for two layers of stacked-end-twisted graphine; A second group focused on three layers.
Joel Wang At the Massachusetts Institute of Technology, which was in a group working on two-fly graphines, says that measuring the kinetic induction was previously prohibited. Because multilayer graphine can only be produced in very small pieces, standard techniques to measure its superconducting currents – such as exposing it in particles or magnetic fields – produced extremely weak signals. Instead, both teams had to innovate a setup, where small graphene flakes were brought in contact with the microwave, while researchers gradually separate different properties like temperature, which are superconductity to be in all It should be kept very low for.
We know that multilaire graphene superconducts because electrons inside it are added, and these couples flow more easily than individual particles. But electrons usually leave each other behind. In fact, how the particles come together and what qualities these couples still do not understand.
“Theory is behind the experiments here (running),” says Miuko Tanaka At the University of Tokyo, which was also in two-ply groups.
For two layers of graphene, his team found that superconducting current is very “stifer” – it opposes more changes – compared to any traditional principle of superconductity. He discovered this discrepancy back into something called Quantum Jormi. In particular, the size of the waves of electrons, which encoded all their properties and potential behavior, seemed to run this foreign type of superconductity.
In the trilliere graphene, the researchers found amazing similarities between the kinetic induction of their samples and the family behavior of completely different superconductors – who maintain their special qualities at a very high temperature.
Because of this, both Banerjee and Tanaka say that these experiments can more than shedding graphine superconducts-they can also reveal the key properties required for the room-Papan superconductors. Physicists have been discovering such materials from decades that their use can fundamentally reduce the energy consumption of many devices.
“We are getting interesting laws that begin to emerge in both these material systems. Perhaps what we are exposing is something deep, ”says Banerjee. Both teams are planning to use equally with other very thin superconductors.
“Recently, there are many new two-dimensional superconductors who are interesting, stunning and unusual,” says Zeu haoAlso at Harvard University, which was researching three-layer graphine. For example, earlier this month a separate team published research that showed that two-layered crystals of a material called tungsten dislikes demonstrate superconductity when layers turn relative to each other.
Meanwhile, Hao’s colleagues Mary credaleNow in NASA Jet Propulsion Laboratory in California, there is an application for already stacked-end-twisted graphine. She is working on particle detectors for space missions, many of which use superconductors. She says that in space flight they can be made small and light – if they are made of multilateral graphene, she says.
