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Study Reveals Microscopic Origins of Surface Noise Limiting Diamond Quantum Sensors

A new theoretical study from the University of Chicago and Argonne National Laboratory pinpoints the microscopic mechanisms that cause surface‑related noise to degrade the quantum coherence of shallow nitrogen‑vacancy (NV) centers in diamond. By coupling density‑functional‑theory surface models with quantum dynamics simulations, the researchers demonstrate that dynamic electron hopping on the surface, rather than static paramagnetic spins, dominates decoherence. They further show that oxygen‑ and nitrogen‑terminated surfaces preserve near‑bulk coherence, whereas hydrogen‑ and fluorine‑terminated surfaces generate strong magnetic noise. The work delivers physics‑based guidelines for engineering quieter diamond surfaces, promising higher‑performance quantum sensors.