For the first time, it has successfully created superconductivity for ordinary materials

For the first time in the history of physics, scientists have created superconductivity (the ability to conduct electricity with zero resistance) for a conventional material. This is considered an important step towards the creation of high-performance superconducting materials at lower costs.

This technique illustrates a theory that has been mentioned since the 1970s, but has not been proven yet. This could pave the way for making current superconducting materials, such as materials used in MRI or magnet trains, with low cost, high performance at higher temperatures.

" Superconductivity is used a lot, most commonly in MRI magnetic resonators , " said Professor Paul CW Chu, who led the University of Houston research group.

If used commercially, superconducting materials could revolutionize many other industries. Not only used in the construction of super-fast transport systems, reducing maximum friction like the Hyperloop system, superconductors also help increase the efficiency of the grid.

Currently, power transmission lines from production to households often cause up to 10% electricity loss. But superconducting materials almost do not cause electricity loss, so power companies will not need to produce more electricity to make up for losses.

One of the major problems with the widespread application of superconductivity is that the superconducting material needs to be cooled to minus 269.1 degrees Celsius to be able to conduct electricity with a resistance of 0. This process is extremely expensive. , both in money and energy.

Aerial superconducting material due to Meissner effect (Photo: Mai-Linh Doan / Wikimedia Commons).

Even the best superconductors currently being tested in the lab have yet to show superconductivity at temperatures higher than minus 70 degrees Celsius. Scientists are still having a headache in increasing the temperature. term (Tcs), ie the highest temperature for a material to exhibit superconductivity, close to room temperature.

For decades, scientists have argued that the optimal way to increase the critical temperature of superconductors is to create superconductivity for materials that do not have this property. This means that if scientists can find a way to turn ordinary materials into superconducting materials, they can make superconductors work at higher temperatures.

Currently, the University of Houston research team has taken the first step, which is to create superconductivity at the contact of two physical phases of the material - also known as the contact surface . They did this for non-superconducting materials, which are calcium iron arsenide (CaFe ₂ As ₂ ).

According to the researchers, "A long-standing method to raise the critical temperature is to utilize natural or artificial contact surfaces. The current work shows that it is possible to raise the critical temperature. for a compound with no superconducting CaFe ₂ As ₂ by superimposing multiple layers of antiferromagnetic or metallic antimatter, this is the clearest evidence to date that it is possible to raise the limit temperature by increasing contact surface for this compound ".

So what is the principle of this technique? The idea that superconductivity can be created or enhanced at the contact surface of two different materials has been around since the 1970s. Although many research teams have tried to prove this could happen. , previous successful superconducting experiments have not yet eliminated the effects of pressure and doping of chemicals that affect test results.

To confirm what happened, University of Houston researchers worked with ambient pressure and using CaFe ₂ As ₂ compound was not doped. They heated the compound to a temperature of 350 degrees Celsius to perform the cooling process, which allowed the material to cool itself down after heating.

This process produces two distinct phases of material inside the CaFe ₂ As ₂ compound because the components of the compound have different cooling rates. While no phase has been shown to be superconducting, the team found superconductivity at the two-phase contact - this proves the theory of contact surfaces is real.

CaFe ₂ As ₂ compound achieves superconductivity at minus 248.15 degrees Celsius, so it has not yielded any major breakthrough for the superconducting industry. However, the same process will be carried out in the next step to create high-temperature superconductors at contact surfaces for higher performance.

Although there is a long way forward to bring this technology into commercial applications, this is a promising step towards developing cheaper and more efficient superconducting materials in the future. .

This research has just been published in the Proceedings of the National Academy of Sciences.