Barnes co-developed (with Nottingham's Matt Brookes) OPM-MEG, the first wearable whole-head magnetoencephalography scanner: a helmet of optically-pumped magnetometer quantum sensors (spin-exchange-relaxation-free Rb vapour cells) that lets patients move naturally during a brain scan, inside an actively-nulled magnetically shielded room. His group has validated the system against cryogenic SQUID-MEG, deployed the UK's first paediatric OPM-MEG epilepsy clinic, and extended the technology to spinal-cord recording and naturalistic/VR paradigms -- a direct human-trials application of a quantum sensor whose femtotesla-scale sensitivity is comparable to the pT/sqrt(Hz)-class sensitivity sought from NV-ensemble magnetometry, but achieved with room-temperature atomic vapour cells rather than solid-state spin defects.

Romalis develops ultra-sensitive alkali-vapor magnetometers operating in the spin-exchange-relaxation-free (SERF) regime, K-noble-gas nuclear spin co-magnetometers used as gyroscopes and for electron/nuclear EDM and Lorentz-violation searches, and Rydberg-atom microwave electric-field sensors; his group's SERF magnetometers were the first used to detect brain magnetic fields. This continues and extends the historical arc of atomic and NV-ensemble quantum sensing (comparable in spirit to DEER/NMR/T1-relaxometry approaches reaching pT/sqrt(Hz) sensitivities), pushing scalar and vector magnetometry toward the fT/sqrt(Hz) and below regime through spin-squeezing and multi-pass optical cells.

Atomic physicist known for spin-exchange optical pumping (SEOP) and its use in ultra-sensitive atomic (SERF-regime) magnetometers, as well as Rydberg-atom quantum information experiments.

Carrie Weidner's GECKO group develops experimental quantum sensing and simulation with cold atoms and hot atomic vapours. Key directions: (1) robust atom interferometry for 6-axis inertial sensing using optical lattice potentials (EPSRC-funded, Infleqtion partnership); (2) magnetic field imaging with squeezed light in hot atom vapour cells (wide-field OPM-type sensing using Faraday rotation); (3) quantum optimal control theory for atom interferometric sensors. The group is establishing a full ultracold atom apparatus for quantum simulation and sensing. Active postdoc positions.