Chinese scientists have recently discovered superconductivity in a nickelate at liquid nitrogen temperature (an inert cryogenic fluid with a temperature of -196℃) under pressure for the first time. It provides a new family of compounds to investigate the high-temperature superconductivity mechanism.

The findings have been published in Nature under the title of "Signatures of superconductivity near 80 K in a nickelate under high pressure".

Screenshot from Nature.

The discovery was made by the research team of Sun Yat-sen University (SYSU), together with Tsinghua University, South China University of Technology, the Institute of Physics of Chinese Academy of Sciences, and Beijing Synchrotron Radiation Facility (BSRF).

The application of superconductors involves information technology, biomedicine, scientific instruments, power, transportation, but most of them are limited by the superconducting transition temperature below 40 K (-233.15℃).

With the public research platform of the School of Physics, SYSU, the research team has found superconductivity at 80 K in La₃Ni₂O₇ single crystals for the first time. (Photo: GDToday)

The team led by Professor Wang Meng from the School of Physics, SYSU spent three and a half years growing single crystals of La₃Ni₂O₇. It was observed that this material has a superconducting transition temperature as high as 80 K (-193.15℃).

Wang said, "Scientists around the world have been exploring for nearly 40 years in the field of superconductivity in nickel oxides. The discovery of superconductivity in this new system exceeds people's expectations. Now, it is possible to conduct research on the mechanism and application of unconventional superconductivity in a new material system."

La₃Ni₂O₇ single crystals were grown by a high-pressure vertical optical-image floating zone furnace. (Photo: GDToday)

Nature reviewers comment that the discovery is "of outstanding importance" and "a breakthrough", saying " The search for superconductivity in Ni-based oxides is an important axis of research at present, and so far superconductivity has only been found in thin films. The discovery of superconductivity in bulk crystals is therefore a breakthrough. The critical temperature of 80 K would put this system in high temperature superconductors."

Professor Zhang Guangming from Tsinghua University said that the new discovery will help to tap into the microscopic mechanism of high-temperature superconductivity, make it possible to design and predict high-temperature superconducting materials, and realize the wide application of superconducting materials at liquid nitrogen temperature.

Wang revealed that the next goal of his team is to achieve superconductivity in nickel oxide materials above the liquid nitrogen boiling point at ambient pressure.

Group photo of Professor Wang Meng's research team. (Photo: GDToday)

Link to the report: https://www.newsgd.com/node_99363c4f3b/b6281bc375.shtml