USTC researchers created a long-lived Schrödinger-cat state, boosting quantum metrology and precision measurements. Their findings open new possibilities for quantum computing and fundamental physics.
A research team led by Prof. Zhengtian Lu and Researcher Tian Xia from the University of Science and Technology of China (USTC) has successfully created a quantum state with a lifetime on the scale of minutes using optically trapped cold atoms. This breakthrough significantly improves the sensitivity of quantum metrology measurements. Their findings were published in Nature Photonics.
In quantum metrology, particle spin serves as a powerful tool for measuring magnetic fields, inertia, and various physical phenomena. It also has the potential to uncover new physics beyond the Standard Model. A high-spin Schrödinger-cat state, a superposition of two maximally opposed spin states, offers unique advantages for precision spin measurements.
In the most massive test to date, physicists have probed a major paradox in quantum mechanics and found it still holds even for clouds of hundreds of atoms.
The researchers say this has important implications for quantum metrology – the study of measuring things under quantum theory.
"Our results represent the first observation of the EPR paradox with spatially separated, massive many-particle systems," the researchers write in their paper.
"They show that the conflict between quantum mechanics and local realism does not disappear as the system size increases to more than a thousand massive particles."
Although we're pretty good at mathematically describing the Universe, our understanding of how things work is patchy at best.
One of the tools we use to close one of the gaps is quantum mechanics, a theory that arose in the early 20th century, championed by physicist Niels Bohr, for describing how atomic and subatomic matter behaves. In this tiny realm, classical physics breaks down; when the old rules no longer apply, new rules must be made.
But quantum mechanics isn't without its flaws, and in 1935, three famous physicists found a significant hole. Albert Einstein, Boris Podolsky, and Nathan Rosen described the famous Einstein-Podolsky-Rosen paradox. READ MORE...
