On March 8, 2023, the world's top magazine "Nature" published a paper by the Ranga Dias team of the University of Rochester. In this paper, their team developed a ternary phase superconducting material composed of three elements: hydrogen, nitrogen, and lutetium. It can achieve about 294K (at about 1GPa (equivalent to about 10,000 atmospheres)). Room temperature superconductivity at about 21°C).
Since this discovery maysubvert many traditional industries, it will bring huge benefits to human scientific civilization. The change shocked the global technology circle for a while.
It is worth noting thatthe paper published by the same team in "Nature" on the same topic in 2020 was retracted from last year . This paper has been cited 632 times by international peers so far!
high profile press releases
On March 11, 2023, the third day after the release of the "Nature" paper, Dr. Dias attended the American Physical Society in Las Vegas and gave a speech titled Observation of Room Temperature Superconductivity in Hydride at Near Ambient Pressure (near Ambient Pressure) Report on room temperature superconductivity observed in metal hydrides at ambient pressure.
Because of his arrival, the lecture was so crowded that security personnel had to prevent more people from entering in advance. Ranga Dias announced at the conference that superconducting technology that can be applied to practical applications at near-ambient pressure has emerged.
Founded in 1899, the American Physical Society (APS) is the second largest physics organization in the world. It publishes more than ten scientific journals and holds more than 20 scientific conferences every year. At the 2023 American Physical Society (APS March Meeting) held in Las Vegas on March 7, physicist Ranga Dias of the University of Rochester and his team reported a milestone breakthrough at the meeting, under "near normal temperature" Room temperature superconductivity was achieved.
At the scene, there were Professor Zhu Jingwu, a pioneer in high-temperature superconductivity, and Dirk van der Marel, a condensed matter physicist at the University of Geneva who had been questioning room-temperature superconductivity.
The following is a Chinese translation of the Dias report summary:
Superconductivity is one of nature's most profound phenomena. However, due to the extremely low temperatures required, this elusive quantum state has yet to revolutionize the scientific community. Therefore, since Kamerlingh Onnes first observed superconductivity in mercury at 4.2 Kelvin more than a century ago, near-ambient pressure superconductivity has become one of the most pursued goals in the scientific community. Over the past decade, high-voltage technology has dominated the search for high-temperature superconductivity. The leading route is achieved through hydrogen alloys under "chemical pre-compression". The superconducting critical transition temperature (Tc) exhibited by the rare earth hydrides LaH10 and YH9 is close to the freezing point of water. We discovered room temperature superconductivity in carbon sulfide hydride (C-S-H) (note: this work has been retracted by Nature), and emphasized that ternary or higher systems may be the key to higher Tc and near-ambient pressure superconductivity . Here, we report recent progress in a new material exhibiting superconductivity under near-ambient pressure conditions. These compounds were synthesized under high temperature and pressure conditions and examined for fully recoverable material and superconducting properties during the compression path. With these materials, the dawn of near-ambient pressure superconductivity and applied technologies has arrived, now opening a direct path to tailoring hydrides for extreme conditions through "materials design."
Revolutionary technologies reshaping the 21st century
Superconducting materials not only have zero resistance characteristics at critical temperatures, but also have characteristics that conventional conductors do not have, such as complete diamagnetism and macroscopic quantum effects, under certain conditions. These properties enable superconductors to achieve large current transmission and obtain strong magnetic fields. , realize magnetic levitation, detect weak magnetic field signals and other applications. Therefore, it is widely used in electronic communications, electric power, transportation, national defense and military, medical equipment and many other fields.
Ranga Dias published a similar paper in 2020, claiming that it successfully created a room-temperature superconducting material with a critical temperature of about 15°C at a pressure of 2.6 million atmospheres, but this paper was later retracted by Nature magazine.
In response, Ranga Dias said in a recent reply to the media, “First of all, this work has been repeated several times in our University of Rochester laboratory and other laboratories, and has third-party observation and independent work verification. Second, our paper has been peer-reviewed and meets the strict standards of this publication; Finally, we have also resubmitted our 2020 paper for another consideration by Nature because of issues raised by the editors of Nature at the time There was no impact on the quality of the experimental data or the conclusions we drew. We are also confident in the quality of the work and experiments performed in 2020."
Ranga Dias said: "This new room-temperature superconducting material will transform the entire superconducting industry, will enable a range of technologies, and will change the way we use, store and transmit energy, not to mention applications in computing, transportation and medicine. There are more applications in devices. We believe this will be a revolutionary technology that will reshape the 21st century."
But he also acknowledged that it will take several years of hard work before his team's discovery of new room-temperature superconducting materials can be applied to the real world at any scale.
Scientists urge to remain "calm"
At the "Interpretation of Room Temperature Superconductivity Phenomenon under 1GPa Pressure" held by the Institute of Physics, Chinese Academy of Sciences on March 10, researchers had some questions about some details of the experimental results of the Ranga Dias team from an experimental perspective.
For example, in another round of resistance measurement results, one sample did not reach zero resistance. The author explained that this result was due to the drift of the measuring instrument, and used function fitting to subtract the background below 220k to obtain zero resistance. "Generally speaking, instrument drift is rare. I have never seen it in experiments." said a researcher from the Chinese Academy of Sciences.
"The color of superconductors close to room temperature is different from known superconductors. It is actually pink, which is completely different from the black and brown colors commonly seen in superconductors." Researchers from the Chinese Academy of Sciences said that if the color is the true color of the sample, it means that even if other research in the future The group can experimentally confirm its superconductivity, and this superconductor should not be a previously known superconductor.
"I was so surprised. Yesterday I received a call from two people in the financial sector whom I didn't know, asking if they could invest or if there were any companies doing this in China. As a scholar of superconducting research, I feel that we shoulder a heavy responsibility." Chinese Academy of Sciences researchers said.
In terms of verification of experimental results, it may take a few weeks or a month or two, or a laboratory will be able to complete the verification of this work. "If this work is proven to be repeatable and true, it will indeed have a greater impact on the superconducting world. However, for a superconducting material to be applied, the critical temperature, critical magnetic field and critical current density must all be It is very important that the three parameters must be high in order to have the basis for large-scale application. Therefore, it is not that finding a room temperature superconductor will be immediately usable, and it will immediately bring about a technological revolution and an energy revolution. It is still far away. It cannot reach this point." said researchers from the Chinese Academy of Sciences.
Listed company’s response
The capital market is even more sensitive to the news. Investors began to study room temperature superconducting technology late at night, and analysts also held meetings in the middle of the night to study it. Recently, room temperature superconducting concept stocks have surged, and many related stocks have reached their daily limit.
On the evening of March 10, Baili Electric issued a stock change announcement stating that the company was paying attention to the hot concept of room temperature superconductivity. The company's main business is power transmission, distribution and control equipment, wires and cables and pumps. The company is not involved in "room temperature superconductivity" related business, nor has it carried out relevant research and development and investment. Beijing Yingna Superconducting Technology Co., Ltd., a subsidiary of the company, is engaged in the research and development and production of bismuth-based high-temperature superconducting wires and has nothing to do with "room temperature superconducting". In 2021, Beijing Yingna Superconducting Technology Co., Ltd. had an operating income of 87,600 yuan and a net profit of -6.0145 million yuan. The current amount of income is small and it is in a state of loss, which will not have a significant impact on the company's performance.
Previously, Yongding Co., Ltd. also announced on the evening of March 9 that the company’s main businesses are communications technology, overseas power engineering, automotive wiring harnesses and superconducting power. It does not involve “room temperature superconducting” related business, and has not carried out relevant research and development and Invest.
According to the investor relations activity record released in September last year, Yongding Co., Ltd. stated that the development of high-temperature superconductors has entered a period of acceleration, and a number of important progresses have been made in key application areas. The company's 2021 annual report shows that the superconducting industry is one of the company's strategic long-term development directions and is an important innovative R&D project in the field of basic science that the company has persisted for more than ten years. The company already has small batch production capabilities and has begun to provide users with superconducting strips with excellent performance indicators. However, the current preparation cost of superconducting strips is still high, and commercialization may be slower than expected, which may lead to uncertainty in the company's ability to achieve its goals.
What is room temperature superconductivity?
Room-temperature superconductors, also known as room-temperature superconductors, refer to materials that can superconduct at temperatures higher than 0°C. Compared with other superconductors, the conditions for room temperature superconductors are easier to achieve daily working conditions. As of 2020, the highest-temperature superconductor is an ultrahigh-pressure carbonaceous hydrogen sulfide system with a pressure of 267 GPa and a critical temperature of +15°C.
The highest temperature superconductor under normal atmospheric pressure is the high temperature superconductor cuprates, which exhibit superconducting phenomena at a temperature of 138 K (−135 °C).
In the past, many researchers had doubted whether room-temperature superconductors were possible. However, the temperatures of superconductors have been increasing repeatedly, and many of them were at temperatures that were not expected or considered impossible in the past.
As early as the 1950s, it was proposed that superconductivity occurs "near room temperature." If room-temperature superconductors could be found, "it would be technologically important, for example, to solve the world's energy problems, to develop faster computers, to be used in advanced storage devices, ultra-sensitive sensors, and many other things." possibility."
We all know that in daily life, when electric current passes through metal wires, it encounters resistance, resulting in heat and energy loss. If there were a material that could completely eliminate resistance without the need for cooling, lossless, high-efficiency, high-speed power transmission and information processing would be possible. This material is a so-called room-temperature superconductor.
Zero resistance effect and Meissner effect of superconductivity (complete diamagnetism)
Superconductivity refers to the resistance of certain materials that suddenly drops to zero below a specific critical temperature (Tc) and has the property of resisting penetration by external magnetic fields (Meissner effect). This wonderful physical phenomenon was first discovered by Dutch physicist Onnes in 1911, and has attracted widespread attention and exploration in the scientific community.
However, all superconductors discovered or created over the past century or so require extremely low temperatures to work. For example, although cuprate high-temperature superconductors are called "high temperature", their Tc is only about -135°C. To achieve such low temperature conditions requires the use of expensive and complex refrigeration equipment, thus greatly limiting the application of superconducting technology in industrial and civilian fields.
Therefore, scientists have always dreamed of finding or creating a true room-temperature superconductor—a material that exhibits zero resistance and perfect diamagnetic properties under normal pressure and temperature conditions. If such a goal is achieved, it will usher in a new era - whether it is saving energy, improving efficiency, reducing costs, creating new functions, expanding new fields, and promoting new development, it will bring revolutionary changes and impacts. .
Age of discovery and critical temperature of typical superconducting materials
For example, in the power system, if room temperature superconducting lines are used instead of ordinary metal lines, the heat and energy loss generated during the transmission process can be greatly reduced, thereby improving the reliability and safety of power supply, reducing power costs and carbon emissions, Even long-distance, large-capacity superconducting transmission networks can be realized. In terms of transportation, if room-temperature superconductors are used to create maglev trains, high-speed, low-noise, low-friction, and low-maintenance operation can be achieved, thereby improving transportation efficiency and comfort, and alleviating traffic congestion and pollution problems. In terms of medical health, if more advanced magnetic resonance imaging (MRI) equipment is developed using room temperature superconductors, higher resolution, lower radiation, and more widely used diagnostic technology can be achieved, thereby improving the level and quality of medical care. In terms of scientific research, if room temperature superconductors are used to build more powerful particle accelerators and astronomical telescopes, it will be possible to explore the structure of matter and the mysteries of the universe more deeply, thereby expanding the boundaries of human knowledge.
In addition to these areas that have been widely discussed and expected, room temperature superconductivity may also bring us some unexpected surprises and innovations. For example, in terms of quantum computing, if quantum bits (qubits) are created using room-temperature superconductors, conditions that can maintain quantum coherence without cooling can be achieved, thereby significantly reducing the complexity and cost of quantum computers and improving their stability. performance and scalability. In terms of communication technology, if new antennas or microwave devices are developed using room-temperature superconductors, lossless, high-sensitivity, high-bandwidth, and high-rate signal transmission and processing can be achieved, thus laying the foundation for 5G or even 6G networks. In terms of military defense, if new radar or laser weapons are designed using room temperature superconductors, interference-free, high-precision, high-power, and high-efficiency detection and attack capabilities can be achieved, thereby enhancing national security.
The direct significance of high-temperature superconductivity is to reduce power transmission losses
If the results of this research are true and reliable, it will mean that the dream of room-temperature superconductivity that scientists have pursued for more than 80 years has become a reality. What follows is that this achievement will change all aspects of human life, no less than the paper "Optical Frequency Dielectric Fiber Surface Waveguide" published by Kao Kun in 1966. The latter pioneered the basic principles of the application of optical fibers in communications, which later led to today's Internet.
Kao Kun, the father of optical fiber
Superconductivity means that electricity can pass through a material with zero resistance, but the temperature prevents this. So, superconducting means zero resistance at a certain temperature. This also means that superconductors not only have the characteristics of zero resistance, but also are completely diamagnetic, allowing the superconductor to lose almost no energy in the process of transmitting current. Each square centimeter of cross-sectional area of the superconducting material can carry a stronger load. current, while general conventional materials consume a large amount of energy during the conductive process.
If superconductivity is achieved at different temperatures, it can be applied to all aspects of people's lives, and some environments and industries have already achieved this goal. For example, superconductivity can be applied to maglev trains, nuclear magnetic resonance imaging, superconducting cables, quantum computers, mobile phone base station receiving signal systems, superconducting filters, etc.
Among them, electricity is the most practical in human life today. If superconducting materials are mature and applied, the loss in the power transmission process can be greatly reduced.
Today's transmission lines are copper or aluminum conductors, and they are usually transported over long distances. In China alone, the annual transmission loss is 15%, or about 100 billion degrees. However, if superconducting materials are used to make power transmission lines and transmit electricity over long distances in a stable zero-resistance superconducting state, theoretically, the loss can be reduced to almost zero. Even if the electrical loss is reduced to 1%, it will greatly benefit production. electricity and energy conservation, reducing polluting energy used for power generation.
Opponent's point of view: This experiment is simply fake
There is a counterargument that the Ranga Dias team cannot reproduce the results of the 2020 C-S-H system paper, and has proposed an even more shocking result in just one year, which is really unconvincing.
The Ranga Dias team uses relatively recognized magnetic susceptibility data to determine superconductivity. (Two reasons for a material to enter a superconducting state: the magnetic susceptibility suddenly changes to -1 under certain conditions, which means it is completely diamagnetic; the resistance suddenly disappears, and it has absolute zero resistance). The reason why the Ranga Dias team's manuscript was withdrawn last time was due to problems with its magnetic susceptibility data processing.
The retraction of "Nature" is that he used a custom method to eliminate noise. The general processing method is to subtract the noise-eliminated data from the original data, and the result is the eliminated noise data. Because the noise is irregular, the data result should be irregular. HoweverHis noise data is very regular, and the spacing between noise points is almost all an integer multiple of 0.16555. Therefore, it was suspected that noise data was used to create fake pictures. There was no corresponding response to the picture and video today.
It feels basically equivalent to,I used a simple pendulum with an external magnetic field to perform a non-attenuation swing experiment, claiming that I have created a perpetual motion machine . He is suspected of processing data in a way that makes the processed data appear to be superconducting data. If so, then the result of his research may not be superconductors, but some kind of beautified data method that inevitably outputs superconducting data results. To change the analogy, I wrote a piece of code that, no matter what I input, would always output the words "The most beautiful woman in the world". Then he told the world that I had discovered the most beautiful woman in the world.
Moreover, the team neither defended the data against critics nor allowed live Q&A sessions. I don’t know if the follow-up “Nature” will withdraw the manuscript again?
If "room temperature superconducting" materials can really be developed, it will indeed be disruptive. Under this premise, high-efficiency power transmission, storage and conversion can be achieved without cooling, thereby saving a lot of energy and costs. In addition, room temperature superconducting materials can also be used to manufacture powerful magnets, sensors, switches, filters and other equipment, providing more advanced experimental methods and tools for physics, chemistry, biology and other scientific fields. For example, room-temperature superconducting materials can be used to build more powerful particle accelerators, nuclear fusion reactors, quantum computers and other facilities. The realization of room temperature superconducting materials may trigger the fourth industrial revolution.
Dias’s own response
In the early morning of March 9th, Beijing time, Ranga Dias, the lead author and paper speaker of the study and assistant professor of the Department of Mechanical Engineering and the Department of Physics and Astronomy at the University of Rochester, accepted the "Daily News" via email Exclusive interview with a reporter from Economic News.
In an exclusive interview, Dr. Dias is confident in his team’s new discovery, which he believes will be a revolutionary technology that will reshape the 21st century. However, he also pointed out that "it will take several years of hard work before our discovery of new room-temperature superconducting materials can be applied to the real world at any scale."
The interview content is as follows:
NBD: How reliable is the new material your team discovered this time? How does it differ in its superconducting properties from a compound of sulfur and hydrogen that your team previously discovered?
Langa Dias: Details of our experimental work are now available in Nature. We are very excited about this new material and the processes required to achieve (room temperature) superconductivity. Of course, more work needs to be done to develop theoretically feasible technologies and applications.
NBD: A similar paper published by your team in 2020 stated that it successfully created a room temperature ultra-high temperature with a critical temperature of about 15°C at 2.6 million atmospheres. However, this paper was later retracted by Nature. Are you confident enough that the new material your team has announced this time will pass muster?
Langa Dias: We are confident this time for several reasons: First, this work has been done in our University of Rochester lab and other The laboratory has repeated it several times, with third-party observation and independent verification of the work; secondly, our paper has been peer-reviewed and meets the strict standards of this publication; finally, we have also resubmitted the 2020 paper for reconsideration by Nature because the issues raised by the Nature editor at the time had no impact on the quality of the experimental data or the conclusions we drew. We are also confident in the quality of the work and experiments performed in 2020.
NBD: If the room-temperature superconducting material discovered by your team finally passes the review, what does this mean for the global superconducting industry? How will this reshape the superconducting industry? What does this mean for the world?
Langa Dias: This new room-temperature superconducting material will change the entire superconducting industry. It will make possible a series of technologies that will change our Ways to use, store and transmit energy, not to mention a wider variety of applications in computing, transportation and medical devices. We believe this will be a revolutionary technology that will reshape the 21st century.
NBD: Your team says that at temperatures of about 21 degrees Celsius, the new material appears to lose any resistance to electrical current. However, achieving superconductivity still requires a pressure of 10 kilobars, which is about 10,000 times the pressure of the atmosphere. But this is far less than the millions of atmospheres typically required for room-temperature superconductors. So, since such a high pressure is required, can the room-temperature superconducting material discovered by your team be applied on a large scale in the short term? What difficulties must people overcome before large-scale application?
Langa Dias: It will take several years of hard work to translate our discovery of new room-temperature superconducting materials into the real world at any scale. These challenges are technical in nature, but they can be overcome.