Home » Superconductivity » Chinese Physics broke a temperature record of superconductivity


Chinese Physics broke a temperature record of superconductivity


Scientists from the Institute of Physics, Chinese Academy of Sciences in Beijing found a very strange behavior of high-temperature superconductor, and at the same time set a temperature record for superconductors based on iron selenite, according to CNews.

As you know, most superconductors lose their electrical resistance at temperatures close to absolute zero, but in the eighties of the last century, physicists were surprised to find that some of these materials super conduct at much higher temperatures is sometimes up to 70 K. If the mechanism of ordinary superconductivity has long been known and well understood, high-temperature superconductivity is still a mystery over which beat laboratories in many countries.

Studied the effect of external pressure on the superconducting properties of iron selenite, the researchers placed a sample between two diamond anvils and began to squeeze it, increasing the pressure. In the normal state loses iron selenite superconducting properties at temperatures above 30 K. Scientists expected that the external pressure by changing the distance between the sites of the crystal lattice of the material, at some point, change its structure, and it will lose its superconducting properties. It happened. Break superconductivity occurred at a pressure of 10 GPa. However, when the pressure was increased to 11.5 GPa, superconductivity suddenly reappeared. Moreover, the effect of the zero-resistance lasted until the record for iron selenite temperature of 48 K.


Why there is such a revival of superconductivity, no one understands. Subir Sahdev from Harvard University (he was not involved in the study) says that it has something to do with a “split personality” selenite, iron, found in other experiments. This material is highly magnetic field with a lot of ordered vacancies (unfilled atom lattice sites), and there are areas with no jobs, and in which the effect is observed superconductivity. Perhaps, says Sahdev at high external pressures magnetic field ejected, and their place is superconducting.

However, he believes that if the still of high-temperature superconductivity has been little known, then we now know even less.

Chinese group hopes to understand how the structure of the superconductor under pressure to investigate its method of neutron scattering. They also plan to “adjust” the structure of a superconductor in such a way as to obtain the transition temperature is not 48, but 77 K – old dream of all solid-state physics, because it is the temperature of liquid nitrogen, which store, and get a lot cheaper than helium.