The mysterious physics of so-called strange metals has baffled scientists for 40 years.. There are already glimpses of understanding the issue, but research continues and discovers more and more inexplicable properties of the substance. A recent study has shown that electric current flows in strange metals in a way that violates the physics we know, and scientists do not yet understand why this happens.
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Strange metals conventionally occupy an intermediate position between dielectrics and conductors. They already have free electrons capable of carrying an electric charge (providing the flow of current), but they have not yet become conductors in the full sense of the word. A synthesis of quantum and classical physics has helped us begin to understand the nature of strange metals. At the same time, he showed that the same effect of electric current, for example, we most likely understood incorrectly.
The modern theory of electric current is based on the transfer of charge by quasiparticles represented by the collective actions of electrons. The discrete nature of the electric current manifests itself in the case of so-called fractional noise, when the current in the network appears in bursts, and not in the form of a uniform charge transfer of a constant value. To find out how current flows in strange metals, scientists created conditions so that they could monitor almost every electron.
The measuring stand was based on nanoconductors made of a compound of ytterbium, rhodium and silicon (YbRh2Si2) with a width of 200 nm and a length of 600 nm. This compound belongs to strange metals and, like other strange metals, has atypical properties near absolute zero. If electric current flowed through this material as we imagine – discretely in groups of correlated electrons in the form of quasiparticles, then nothing strange would happen. However, during the experiment, scientists were convinced that the current continued to flow smoothly without fluctuations characteristic of fractional noise, like water along a wide trench.
In other words, the charge was partially transferred as if without the participation of electrons, which seems incredible. Perhaps the same thing happens in metals, and the charge carrier is something other than electrons. Undoubtedly, quantum effects are manifested in this, but physicists have yet to explain how.
The answer to this question will help to bring closer the discovery of superconductivity at ordinary temperatures, because one of the fundamental properties of strange metals is the behavior of resistivity near absolute zero, which is completely different from metals. For metals it changes abruptly from zero to high, but for strange metals, instead of a jump, it grows gradually and linearly. If only we could reach it a little to high temperatures, and everyone would be happy in the energy sector.