A tiny spin change just flipped a famous quantum effect

When quantum spins interact, they can produce collective behaviors that defy long-standing expectations. Researchers have now shown that the Kondo effect behaves very differently depending on spin size. In systems with small spins, it suppresses magnetism, but when spins are larger, it actually promotes magnetic order. This discovery uncovers a new quantum boundary with major implications for future materials.

source https://www.sciencedaily.com/releases/2026/01/260121233400.htm