Last week, a Korean research team published a paper on room-temperature superconductors, unexpectedly sparking a global craze over superconductivity. Today, let’s ride the wave and introduce the history of superconductors!
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Why are superconductors so highly anticipated?
Superconductivity is an astonishing physical phenomenon, where a material exhibits zero electrical resistance and expels magnetic fields under specific conditions. This means that, in the process of transmitting electrical current, as long as there is no external interference, the current can flow indefinitely without any loss. This eliminates transmission losses in power lines and significantly reduces the demand for power generation.
The development of this field is intertwined with many renowned scientists, significant experimental discoveries, and groundbreaking theoretical advancements. Let’s explore the history of superconductors together, and discover how this once mysterious phenomenon has gradually been unveiled and applied.
History of superconductors
The history of superconductors dates back to the late 19th century. In 1881, Dutch physicist Heike Kamerlingh Onnes successfully cooled helium to near absolute zero (-273.15°C or 0K). In this extremely low-temperature environment, Onnes unexpectedly observed that the electrical resistance of certain metals suddenly vanished. This marked the first discovery of the superconducting phenomenon. Onnes continued his research and found that this phenomenon was not limited to metals alone but also included some compounds and alloys.
However, the mysteries of superconductors were not fully understood at the time. It wasn’t until 1933 that Swiss physicists Walter Meissner and Robert Ochsenfeld collaborated to propose the famous Meissner-Ochsenfeld effect, which revealed the magnetic field expulsion in superconductors, commonly known as the “Meissner effect.” This discovery not only deepened the understanding of superconductors but also laid the groundwork for their future applications.
As research into superconductors progressed, scientists sought to explain the nature of the phenomenon. In 1957, John Bardeen, Leon Cooper, and Robert Schrieffer introduced the famous BCS theory, which explained the mechanism of electron pairing in superconductors. The BCS theory became a crucial framework for understanding the behavior of low-temperature superconductors and established the theoretical foundation for further research.
However, early superconductors could only exhibit superconductivity at extremely low temperatures, limiting their practical applications. It wasn’t until 1986 that the discovery of high-temperature superconductors caused a sensation in the scientific community. The research team, including Swiss physicist Georg Bednorz and German physicist K. Alex Müller, found that certain copper oxide compounds could achieve superconductivity at relatively higher temperatures. This breakthrough suggested that superconductors might no longer be confined to extremely low-temperature environments, paving the way for more practical applications.
Since then, significant progress has been made in the study of high-temperature superconductors. Scientists have discovered various high-temperature superconducting materials and have begun to unravel some of the mysteries surrounding them. These materials can achieve superconductivity at the temperature of liquid nitrogen, opening up new possibilities for superconducting technology in areas such as power transmission, magnetic levitation, and electronic components.
The applications of superconductors continue to expand. In power transmission, superconducting wires can greatly reduce energy losses during current transmission, improving energy efficiency. Additionally, superconducting magnets play a crucial role in medical diagnostic technologies like Magnetic Resonance Imaging (MRI) and have potential applications in scientific research, particle accelerators, and quantum computing.
In summary, the development history of superconductors has gone from the early observation of phenomenon to the later realization and implementation.
The reason why superconductors are so highly anticipated
As mentioned earlier, the reason why room-temperature superconductors are so eagerly awaited is that current superconductors require extreme conditions to function, making their practical use challenging. If room-temperature superconductors were to emerge, they could potentially revolutionize our technological development and usher in a new era of superconductivity.
