Mitchell leads quantum-enhanced (spin-squeezed) atomic magnetometry, microfabricated vapor cells, and multichannel ZULF NMR with atomic-magnetometer arrays, probing fundamental sensitivity limits. This vapour-phase approach reaches femto-to-picotesla sensitivities complementary to NV-center diamond ensemble quantum sensors (DEER, nano-NMR, T1 relaxometry) that operate near the pT/sqrt(Hz) regime.