Southeast Asia Information Port News (www.dnyxxg.com) – A team from the University of Science and Technology of China (USTC) recently successfully constructed the world's first quantum sensing network based on atomic nucleus spin, providing a breakthrough tool for searching for the universe's "invisible neighbors."
On the morning of January 29th, the international academic journal *Nature* published this groundbreaking research result, which represents a new peak in the sensitivity of dark matter detection. This achievement was obtained by the team of Professor Peng Xinhua and Professor Jiang Min from the Spin Magnetic Resonance Laboratory at USTC.
In the vast universe, ordinary matter such as stars and planets visible to the naked eye accounts for only 4.9% of the total mass of the universe. Dark matter, which accounts for a staggering 26.8%, acts like an "invisible neighbor"—it does not emit light, does not interact electromagnetically with ordinary matter, but can influence the motion of galaxies through gravity, making it a crucial component of the universe's structure.
Axions, as a popular candidate for dark matter, may form fields with topological defects resembling "cosmic wrinkles," which scientists figuratively call "dark matter walls." When Earth passes through this "invisible wall," axions may interact extremely weakly with the atomic nuclei in the quantum sensor, producing a fleeting signal. Capturing this signal is as difficult as precisely distinguishing the sound of a specific snowflake landing in a bustling square.
To overcome this detection challenge, the research team equipped the quantum sensor with two "hardcore tools": first, storing the fleeting signal in a near-minute-scale nuclear spin coherent state, significantly extending the signal detection window; second, using self-developed quantum amplification technology to amplify the weak signal a hundredfold, making even the slightest trace easily detectable.
The team also deployed five ultra-sensitive quantum sensors in Hefei and Hangzhou, precisely synchronized via satellite time, constructing a distributed detection network. This network configuration greatly filters out false alarms, achieving unprecedented reliability in the detection results.
After two months of continuous observation, although the team did not capture a definitive signal of the "dark matter wall" crossing, they made crucial progress: providing the most stringent constraint criteria for this dark matter model across a wide range of axion masses.
The precision of the detection range for some mass intervals is 40 times higher than that obtained by astronomers using supernova observations, marking the first time that laboratory detection precision has surpassed astronomical observation.
Reviewers for *Nature* highly praised the work, stating, "This work provides a powerful tool for particle physics and astrophysics research and will inspire a new wave of research."
According to the researchers, this research not only opens up new pathways for dark matter detection, but its networked, distributed detection approach can also be used in conjunction with gravitational wave observatories to search for more cosmic mysteries in the future.
Currently, the team plans to further expand the coverage of the "quantum detection network" by increasing its detection sensitivity by another four orders of magnitude through global networking and space deployment, allowing this "detection network" to continue exploring deeper into the universe. (End)
