People in China are obsessed with major breakthroughs in technology, first the chatbot ChatGPT, now the room-temperature superconductor.
Recently, a video from Huazhong University of Science and Technology (HUST) illustrating the partial levitation of a LK-99 sample has gone viral, generating 9.7 million views on Bilibili, China's equivalent to YouTube, within 3 days.
LK-99 is a lead-based compound that was synthesized by a group of researchers from South Korea in late July 2023. The team has claimed that the compound is a room-temperature superconductor because it is able to conduct electricity with zero resistance at ambient pressure and temperatures below 400 K (127 °C or 260 °F).
This is a significant finding, as currently available superconductors either require cooling to very low temperatures, typically between 20K to 77K (-253°C to -196.15°C or -423.67°F to -321.07°F), or can only work under extremely high pressures, such as near the center of the Earth.
If LK-99's claims are true, it could revolutionize the tech industry, with potential applications in high-speed maglev trains, MRI machines, and quantum computers.
The video's popularity also sparked a frenzy in the stock market, with investors pouring into companies related to superconductors, like "Henan Zhongfu Industry Co.,Ltd," "Western Superconducting," and "Jiangsu Etern Co," resulting in surging stock prices.
However, while the general public exudes excitement, experts remain cautious and skeptical. Given the field's history of false alarms, problems with the quality of South Korea's paper on LK-99, and the unusual circumstances of its publishing, most experts remain skeptical of the finding.
To figure out what was really going on, researchers in China rushed to replicate the experiment. Some of them claimed partial success, while others ended in failure:
- Beihang University first replicated the experiment and uploaded a paper to arXiv on July 31, showing that LK-99 is not superconductive. The paper noted that the material exhibited semiconductor-like rather than superconductor-like properties.
- Next came an August 1 experiment at Huazhong University of Science and Technology, showing that LK-99 can be partially levitated, promising the potential of room-temperature non-contact superconducting maglev.
- On the evening of August 2, experiments from Qufu Normal University showed that the sample still has significant resistance in the range from room temperature to 50K (-223.16°C or -369.67°F), which is far from the expected "room temperature superconducting" zero resistance characteristic.
- August 3, Southeast University observed zero resistance in the LK-99 sample, but only when it was cooled to 110K (-163.15°C or 261.67°F), not room temperature. Also, the resistance drops gradually, rather than the sharp drop that should be expected in superconductors. The other five LK-99 samples synthesized by the research team did not show superconductivity but exhibited semiconducting properties.
Adding to the skepticism, Korea JoongAng Daily, a mainstream media in South Korea, reported today that the Korean Society of Superconductivity and Cryogenics has concluded that LK-99 is not a superconductor because it did not exhibit the Meissner Effect - the phenomenon in which a superconducting material expels all external magnetic fields, causing it to levitate in a magnetic field.
In light of most recent developments, shares of some so-called superconductor-related stocks experienced a significant drop in China's stock market on Thursday, signaling a momentary pause in the frenzy.
Similar scenes unfolded in the US and South Korea, where people demonstrated excessive enthusiasm for the potential breakthrough in the solid-state physics sector. Social media platforms buzzed with passionate discussions, related stocks soared with increased interest, and some people even attempted to replicate the experiment on their own.
As The New York Times put it, “LK-99 is the superconductor of the summer”.