The Joule's law of middle school physics tells us that the current passing through the resistor will generate heat. In this way, a large amount of energy will be lost as heat. And there is a mysterious material that can crack this "curse", it is a superconductor. In superconductors, the transmission of electric current can ignore the resistance, there will be no loss, and the efficiency can reach 100%. Therefore, superconductors are regarded as an important revolutionary material. Once successfully developed, it will bring huge economic benefits and will greatly promote the development of science and technology.
A superconductor is a conductor whose resistance is zero below a certain temperature. Zero resistance and complete diamagnetism are two important characteristics of superconductors. The temperature at which the resistance of a superconductor turns to zero is called the superconducting critical temperature. According to this, superconducting materials can be divided into low-temperature superconductors and high-temperature superconductors. The high temperature (greater than -200°C) here is relative to absolute zero, which is actually far below the freezing point of 0°C.
Although superconductors have been used in the fields of MRI, particle accelerators, and quantum computing, they must be cooled to extremely low temperatures to achieve a superconducting state. This means that practical applications need to rely on expensive cryogenic liquids, such as liquid helium, to maintain a low temperature environment. Therefore, the cost of superconducting applications has increased sharply, and even the cost of maintaining low temperatures must far exceed the value of the material itself.
For a century, scientists have been seeking to increase the critical temperature of superconducting materials. And room temperature superconductivity has become the holy grail in the hearts of physicists! As more and more superconducting materials are discovered, the record of the highest critical temperature is constantly being refreshed, gradually moving towards the goal of room temperature. At present, the highest critical temperature record for high-temperature superconductors is 250K (-23°C) maintained by the team of A. P. Drozdov of Max Planck Institute of Chemistry in Germany.
Recently, this record was refreshed again! On October 14, 2020, "Nature" published online a major breakthrough in the field of room temperature superconductivity by Ranga P. Dias and others from the University of Rochester: Room-temperature superconductivity in a carbonaceous sulfur hydride
Crossing the node of zero degrees (273K), the superconductivity of the C-S-H system at a temperature of 288K (about 15°C) was achieved in one fell swoop! Moreover, this is also the first report of an organic superconducting system containing three elements instead of two!