Recently, according to the South China Morning Post, a well-known international media outlet in Hong Kong, a team of scientists led by China has discovered a new quantum magnetic material with "ultra-solid" properties that can be used to create ultra-low temperature environments for high-tech applications such as quantum computing.
Quantum computing track
Quantum computing is a technology that uses the principles of quantum mechanics to perform calculations, and it has the potential to surpass traditional computers to solve some currently unsolvable problems, such as cryptography, artificial intelligence, materials science, etc.
But to enable quantum computing, an extreme environment needs to be created, known as ultra-low temperatures, which are near-absolute zero, allowing qubits to remain stable and controllable.
However, the main way to achieve ultra-low temperatures at present is to use liquid helium as a refrigerant, a scarce and expensive resource that is largely dependent on imports. Against the backdrop of the U.S.-China tech war, China also faces the threat of U.S. restrictions on the export of dilution refrigerators, a key piece of equipment for manufacturing ultra-low temperature environments.
Therefore, finding a refrigeration system to replace liquid helium is of great significance for China to accelerate the development of quantum technology and improve its national security and competitiveness.
Recently, an international team of researchers led by Chinese scientists published a paper in the journal Nature, announcing that they have discovered a new ultra-solid material that can be used to create ultra-low temperature environments, thus opening up the possibility of high-tech applications, such as quantum computing.
This research not only provides a direction for solving the problem of helium shortage, but also opens a new window for exploring the mysteries of fundamental physics.
Discovery and characterization of new materials
The international team, led by researchers at the Chinese Academy of Sciences laboratory in Beijing, set out to find a solid-state material that could achieve large energy changes by changing its state to achieve the effect of cooling.
After years of experimentation, they discovered a cobalt-based quantum magnetic material, which is a "super-solid" material, meaning it has a solid structure, but also exhibits fluid properties.
A supersolid state, a non-viscous state of matter that has both the rigidity of a solid and a superfluid, is a very rare and mysterious phenomenon that physicists have been searching for for half a century.
The formation of supersolids requires a very low temperature to allow the interaction between atoms to reach a level of equilibrium, so that the atoms can maintain an orderly arrangement and flow freely.
The scientists say they have also observed that the material cools to temperatures below 1 Kelvin, potentially being used to achieve ultra-low temperatures. The lowest possible temperature in physics is minus 273 degrees Celsius, or 0 Kelvin (minus 459 degrees Fahrenheit), according to the third law of thermodynamics.
Physicists define ultra-low temperatures as between 0 and 4.2 Kelvin, which is the range needed to develop cutting-edge technologies, including quantum computing.
"This is really an emerging frontier," said a professor at the Chinese Academy of Sciences' National Laboratory for Condensed Matter Physics, who is one of the study's co-corresponding authors.
Scientists have only seen the potential to use the solid state to achieve ultra-low temperatures in recent years, he said, and this research has only been conducted by a handful of scientists around the world.
Applications and impacts of new materials
The study is significant for China, which currently relies on importing helium from countries, including the United States, as a refrigerant. And in the context of the Sino-US technology war, China also faces the threat of the United States restricting the export of dilution refrigerators to it, which is a key equipment for creating ultra-low temperature environments.
The shortage of helium, especially helium-3, is a challenge for China as it accelerates the development of quantum technology. In 2022, 94% of China's helium was imported, most of which came from Qatar, followed by the United States and Australia.
According to Professor Sun, China "simply does not have helium-3 at all and almost always relies on Russia and the United States" for this isotope.
In the context of the U.S.-China technology war, it is becoming increasingly difficult for China to obtain dilution chillers from overseas, which Professor Sun said has "seriously hindered the development of quantum technology in China".
Beijing has made it a national priority to support Chinese production of this critical technology and has invested heavily in it. In October 2023, quantum computer company Origin Quantum became the latest Chinese company to announce the production of dilution refrigerators, according to the official Science and Technology Daily.
Professor Sun said the team has developed some equipment to replicate and apply their experiments in certain environments, but noted that there is still a long way to go and some engineering issues to overcome.
If this new material can be successfully used to create ultra-low temperature environments, then it will bring huge advantages to China's quantum technology development, not only to reduce costs and dependency, but also to improve efficiency and stability.
Quantum technology is a disruptive technology, which can change the status quo in the fields of information processing, communication, security, and detection, and has an important impact on the country's scientific and technological innovation, economic development, and international competitiveness.
In addition, this research may also be a starting point for further discussion and research into fundamental physics.
"For half a century, it was thought that supersolids existed, and now we have some evidence," says Sun, "and scientists may be inspired to look for new evidence in other materials, which could eventually advance physics." ”
Supersolid state is a complex phenomenon involving quantum mechanics, condensed matter physics, statistical mechanics and other fields, which is of great value for understanding the nature of matter, exploring the mysteries of the universe, and discovering new physical laws.
This research not only provides a new option for refrigeration technology, but also opens a new window for the exploration of physics.