Direct Raman observation of the quantum metric in a quantum magnet
Researchers used direct Raman spectroscopy on a quantum magnet to observe both Berry curvature and quantum metric simultaneously. They found that field-odd chiral splitting ($Δω$) and field-even center shift ($δω$) collapse onto a single curve, proving they originate from the same microscopic interaction. This establishes Raman spectroscopy as an all-optical probe for both quantum geometry components.