"Room-temperature superconductivity" is once again sweeping the globe! Will the "Holy Grail" of physics usher in the fourth industrial revolution?

Will we witness the arrival of the superconducting era?

Since the end of July, the "room-temperature superconductivity" storm has swept the world. A Korean team uploaded two papers on arXiv, claiming to have successfully synthesized the world's first room-temperature superconductor - modified lead phosphor apatite crystal structure (LK-99), shocking the world.

It is reported that LK-99 is a hexagonal structure slightly modified from lead phosphor apatite, with a small amount of copper introduced, allowing it to exhibit superconductivity below 127 degrees Celsius. The chemical formula is written as:

Room-temperature superconductors are considered one of the "Holy Grails" of modern physics, and the "heavyweight" dropped by the Korean research team has once again ignited the physics community.

Some analysis points out that what makes LK-99 from the Korean team "even more incredible" is that it not only solves the temperature problem but also does not require "high-pressure assistance." And the Tc of 127℃ is not only a significant improvement compared to previous research but more importantly, it greatly expands the applicable temperature range.

In simple terms, this futuristic technology allows electrons to pass quickly at room temperature, without resistance, without energy consumption, and will disrupt the existing power system. The realization of room-temperature superconductivity will profoundly transform the current energy system, information processing and transmission system, and bring progress in many fields such as medical testing, high-speed transportation, and even controlled nuclear fusion.

Currently, it is generally believed in the industry that the preparation process of LK-99 seems relatively simple, under normal temperature and pressure conditions, using the "hand-rolled material" method, which has sparked hope amidst astonishment and skepticism - what if superconductivity is really that simple, wouldn't it be a huge breakthrough?

Therefore, whether studying materials or not, everyone is eagerly watching the reproduction process in major laboratories. The first batch of repeated experimental results of LK-99 is out: the theory is feasible but levitation or superconductivity has not been reproduced.

On July 31st, at 16:13, researchers from Beihang University submitted a paper on arXiv, stating that the experimental results did not find the superconductivity of LK-99. The LK-99 sample they obtained had X-ray diffraction patterns consistent with the Korean team, but they could not detect significant diamagnetism or observe magnetic levitation phenomena. From the electrical transport properties, LK-99 appears more like a semiconductor; and from the resistivity, LK-99 does not exhibit zero resistance like a superconductor.

Almost simultaneously (July 31st, 17:58), researcher Sinead M. Griffin from Lawrence Berkeley National Laboratory (LBNL) submitted a paper titled "Origin of correlated isolated flat bands in copper-substituted lead phosphate apatite" on the preprint website arXiv. Griffin stated that they used Density Functional Theory (DFT) and GGA+U method for calculations, providing theoretical basis for the so-called "room temperature and atmospheric pressure superconducting material" by the recent Korean team. She believes that the calculation results show that LK-99 may possess superconducting properties, with characteristics of high-temperature superconductor Fermi level flat band.

On the afternoon of August 1st, a domestic internet blogger released a video claiming that the team from Huazhong University of Science and Technology has successfully synthesized the LK-99 "room temperature superconducting crystal" that can levitate magnetically, which has already been verified by the Meissner effect.

However, according to him, although this crystal exhibits diamagnetism, it is relatively weak and does not have the so-called "zero resistance". The overall performance is similar to that of a semiconductor curve. He believes that even if LK-99 possesses a superconducting phase, it is only a trace amount of superconducting impurities and cannot form a continuous superconducting path.

While the authenticity of the research by this Korean team has yet to be determined, American research companies quickly followed suit, not only claiming to have discovered room temperature superconductors but also stating that they have obtained relevant patents.

In the early morning of August 1st, Beijing time, Taiji Quantum, located in the United States, released photos stating that they have discovered a new type of room temperature superconducting material, which is a graphene foam material that is very fragile. The company has obtained an important patent related to room temperature superconducting materials, which may mean that this material will enter the production stage.

Paul Lilly, CEO of Taiji Quantum, said, "We are pleased to announce that we have finally obtained our patent for the room temperature Type II superconductor."

After the news came out, the US superconducting stocks continued to rise in pre-market trading, with the increase reaching 130% at one point.

In the following days, more replication experiment results will emerge. Researchers from all over the world will work together to verify whether humanity can achieve the holy grail of room temperature superconductivity and enter a new era.

What exactly is superconductivity?

Over 100 years ago, the Dutch physicist Kamerlingh Onnes opened the door to superconductivity for humanity. In 1911, Onnes discovered during his research that the electrical resistance of the metal mercury (Hg) suddenly dropped to zero when the temperature dropped below 4.2K, and this was not caused by any experimental error. Since then, mercury has become the first superconductor discovered by scientists, with a superconducting Tc of 4.2K. The so-called superconducting Tc refers to the superconducting transition temperature, which is the temperature at which a superconductor transitions from the normal state to the superconducting state.

Zero resistance is one of the basic characteristics of superconductors. In addition, another important basic characteristic is the Meissner effect. More than 20 years after Onnes' discovery, Meissner found that when a material is in the superconducting state, its internal magnetic field is zero, exhibiting complete diamagnetism, which is also known as the Meissner effect.

The phenomenon of superconductivity is considered one of the greatest discoveries of the 20th century.

However, up to now, the practical applications of superconductors are mainly limited to a few specific scenarios such as magnetic levitation, because they usually need to be cooled to extremely low temperatures and subjected to high pressures to become superconducting. The Korean research team mentioned that since Onnes discovered superconductivity, scientists have been searching for room temperature superconductors.

Therefore, one of the "Holy Grails" of modern physics is to find a "room temperature superconductor" that exhibits superconducting properties at normal temperature and pressure.

In its research report, Zheshang Securities pointed out that the transition temperature of most superconducting materials is below 40K (-233℃), which limits their wide application in energy, medical, information, and precision measurement fields. Currently, only two unconventional superconducting material systems, copper oxide superconductors and nickel oxide superconductors, have been found to have transition temperatures in the liquid nitrogen temperature range of 77K (-196℃).

The superconducting material system announced by the Korean research team exhibits superconductivity at "room temperature and pressure" (transition temperature of about 400K (127℃)). If successfully reproduced, this will be a revolutionary breakthrough in the field of superconductivity.

Why is "room temperature and pressure superconductivity" so exciting globally?

In fact, room temperature superconductivity and related "research achievements" are not new. As early as 2018, two Indian scientists claimed that a mixture of gold and silver nanoparticles exhibited superconducting properties at 13℃. However, this research was abandoned after the authors published a correction in May 2019.

In March of this year, the Diaz team at the University of Rochester in the United States claimed to have discovered room temperature superconductivity, but it was soon questioned by multiple experimental teams, and the article was retracted amid the doubts.

Why do humans desire room temperature superconductivity so much?

First, let's talk about its significance. Some analysts believe that "if someone can break through room temperature and pressure superconductivity and eventually achieve commercialization, its enormous value is likely to usher in the fourth industrial revolution." The utilization efficiency of energy has greatly increased, eliminating the need for fossil fuel extraction and protecting the environment, while artificial intelligence is rapidly advancing...

"Superconductors" can ensure zero resistance at specific temperatures, possessing characteristics such as zero resistance and complete diamagnetism. They can be widely applied in energy storage, maglev trains, power transmission, nuclear magnetic resonance, and other fields.

China Post Securities pointed out that room-temperature superconductivity means that "long-distance lossless power transmission" can be achieved, which will trigger a new round of global power network infrastructure construction. In addition, breakthroughs are expected in superconducting magnets, superconducting cables, and maglev trains.

Taking maglev trains as an example, Japan's low-temperature superconducting maglev technology uses superconducting materials to make superconducting coils. By installing a refrigeration system on the train, the superconducting coils can be maintained at a low-temperature superconducting state.

When current is transmitted through the conductor, there is no heat generation, and the current loss is minimal. The magnetic force generated by the current allows the train to levitate and move forward. However, the requirement for ultra-low temperatures in superconductivity remains a challenge for widespread adoption of related technologies.

Initially, superconductors required temperatures close to absolute zero, typically achieved using liquid helium at a cost of several hundred yuan per kilogram. Later, "high-temperature superconductors" (referring to superconductors with critical temperatures in the liquid nitrogen range) were developed, which can be achieved using liquid nitrogen at a cost of around 4 yuan per kilogram, similar to the cost of mineral water.

If breakthroughs are made in room-temperature and atmospheric-pressure superconducting materials, it will undoubtedly bring about changes in many fields such as energy, transportation, computing, and medical diagnostics. Zheshang Securities pointed out:

More efficient energy transmission, conversion, and storage: Superconducting materials, with their zero-resistance characteristics, can transmit electricity without loss, greatly improving energy transmission efficiency, stability, and reliability.

Faster transportation methods: The improved energy transmission efficiency brought by superconducting materials and the possibility of reducing costs for maglev trains will directly impact the transformation of high-speed transportation methods.

Faster information processing speed: Superconducting materials exhibit high quantum characteristics in low-temperature environments and can be used to build quantum computers with computing speeds far exceeding existing computers, potentially bringing about tremendous changes in the field of information processing.

Advanced treatment methods: Superconducting materials have extensive applications in the medical field, such as MRI and superconducting coils. The emergence of room-temperature and atmospheric-pressure superconducting materials will make it possible to miniaturize and make medical equipment portable, promoting the development of medical technology.

Dongwu Securities believes that it will take some time for experimental results to transition from the laboratory to commercial applications, so even if room-temperature superconducting materials are verified, it is difficult to determine the commercialization timeline for room-temperature superconductivity:

The discovery of low-temperature superconductivity dates back to the 1910s, but it was not until the 1980s that it was maturely applied in the field of medical nuclear magnetic resonance. High-temperature superconducting materials were discovered in the late 1980s, but due to the complexity of material preparation processes, it took 35 years for them to enter the market.

Currently, the production cost of room-temperature superconducting materials is high, and mass production techniques have not yet been developed. Furthermore, the stability of these materials still requires extensive verification. Therefore, even if room-temperature superconducting materials are verified, it is difficult to determine the commercialization timeline for room-temperature superconductivity. Currently, the superconducting technologies that can achieve large-scale commercialization in the industry are still mainly focused on low-temperature and high-temperature superconductivity.