Nature Physics, Published online: 29 July 2024; doi:10.1038/s41567-024-02563-4
Spin-squeezed states are a resource for quantum-enhanced precision measurement. However, the theoretical foundations for scalable spin squeezing — where quantum enhancement grows with system size — have only been established for systems exhibiting all-to-all interactions. Now, by unveiling a connection to finite-temperature magnetism, scalable squeezing is extended to locally interacting systems.