A major breakthrough in the 20th century was the invention of semiconductors. Now, in the 21st century, they might emerge to be the sole subject of interest. In simple terms, superconductors are materials exhibiting zero resistance and disposition of any form of magnetic field. In the 20th century, with the emergence of semiconductors, resistance emerged to be a topic of concern among scientists.
In practical uses, resistance has been a cause of the production of heat which has raised many concerns in the society. The loss of energy in the form of heat during its transfer is a widespread concern among intellectuals. Various means had been used to solve this problem, either by using wires of different thickness and size or using a wire of lower resistance. Despite the incessant efforts, there had been no permanent solution to defying resistance in the wire. That was until the Dutch physicist, Heike Kamerlingh Onnes noticed an abnormal behavior in mercury at a very low temperature of 4.2K. Following this discovery, many materials portrayed a similar behavior, becoming superconductors at their own unique temperatures.
Following are some examples of superconductors:
1. Lead at 7 K
2. Niobium at 10 K, and
3. Niobium nitride at 16 K and several other compounds.
Another property that was noticed is that there is no presence of any magnetic field once the temperature barrier is crossed which is known as the Meissner Effect. It refers to the prevalence of perfect diamagnetism. However, by the 1980s, some materials not only exhibited superconductivity, but some of them also did at significantly higher temperatures. Elements of lanthanum and barium broke the well-established temperature records, finding superconductors at temperatures beyond 30 K. This record was set by the new material: Yttrium-Barium-Copper-Oxide. As a result of this discovery, it was not necessary to use liquid helium or liquid nitrogen to make superconductors and the process was made a lot easier. The temperatures for production of superconductors continued to rise until about 200 K. However, a time came when the superconductivity temperature failed to pass the 200 K mark. This resulted in the development of superconductors to halt for several decades. At this point of time, it was believed that it was impossible for superconductors to cross the temperature barrier of 200 K.
The first humongous breakthrough after several decades came about in 2015, when a group of scientists took a simple molecule, Hydrogen Sulphide (H 2 S) and applied a staggering pressure of 155 GPa on it. Under these conditions, the 200 K barrier was cracked. This was a great promise to many physicists for a better future which can harness the power of superconductors to the advantage of mankind.
All this ramble about superconductors was for the ultimate benefit of society. With the help of superconductors, it is possible to create miniature phones, laptops and devices. On the other hand, highly efficient electrical infrastructure devoid of any resistance can be used for housing and various other purposes. This can help us to lead an energy efficient revolution and bring about a monumental change in society. The crucial task at hand is to discover a superconductor that can exist at room temperature (25 degree 2 celsius) and at relatively lower pressures. Once this is achieved, the dream for an ultimate society filled with infinite possibilities will no longer remain a possibility.
Bibliography:
- Siegel, Ethan. “How Close Are We to the Holy Grail of Room-Temperature Superconductors?” Forbes, 9 Nov. 2022, www.forbes.com/sites/startswithabang/2021/07/07/how-close-are-we-to-the-holy-grail-of-room-temperature-superconductors/?sh=421597286650.
- Grant, Ian. “A Brief History of Superconductivity.” Superconductivity - History, www.chm.bris.ac.uk/webprojects2000/igrant/history.html. Accessed 23 July 2023.
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