Quantum Soup of Atoms: A New View on Spin Liquid ⚡ экспресс
Scientists on a quantum simulator of 114 atoms in a kagome lattice (a frustrated geometry that prevents spins from aligning harmoniously) gently prepared a disordered correlated state — a quantum spin liquid. The measured spin correlations matched well with the Dirac spin liquid model, and the entropy density turned out to be close to that observed in solid frustrated magnets at liquid nitrogen temperature. This is the first direct comparison of a 'liquid' state of atoms with theory and an important step toward understanding quantum disorder.
Physicists took 114 rubidium atoms, cooled them to near absolute zero (as in experiments with liquid helium), and neatly arranged them in a honeycomb pattern. They then smoothly adjusted the interaction strength, as if slowly turning up the heat under a pot. On low 'flame,' the atoms stayed in orderly magnetic rows, like a crystal. But as disorder increased, the rigid order melted away, giving way to a liquid state where each atomic magnet spun incessantly, together resembling whirlpools in a boiling water.
This magnetic broth, known to theorists as a spin liquid, behaves astonishingly: the excitations that arise in it race without resistance, like light—mass is no obstacle for them. This is exactly the behavior predicted by Richard Feynman when he contemplated quantum simulators. Tests showed that this soup is not mere chaos, but a long-sought state that could hold the key to building quantum computers. It turns out that even from atomic disorder, you can cook up an ideal medium for computation.
🎯 Excitations in this magnetic liquid move without resistance, as if they have no mass—just like light. That's why it's called an 'ideal quantum medium.'