O'Hare is a dark-matter phenomenologist whose work sits unusually close to instrumentation: he is the principal theorist of the 'neutrino fog' that limits direct-detection experiments, of directional dark matter detection (using the daily modulation of the WIMP wind to distinguish signal from background), and of the axion and ultralight dark-matter searches that increasingly rely on quantum sensors — haloscopes, comagnetometers, NMR-based searches and atomic magnetometers. He writes the sensitivity projections that tell experimentalists which quantum sensor to build. Positioned against the established body of NV-ensemble quantum sensing work — DEER, nanoscale NMR and T1 relaxometry protocols operating at pT/sqrt(Hz) field sensitivity — the axion/ALP search programme he works on consumes spin-ensemble magnetometry directly: CASPEr-class experiments are, in effect, precision NMR magnetometers operating far below pT/sqrt(Hz), and his phenomenology sets the sensitivity targets they aim at. Theory PI with strong experimental engagement.

Quiney (currently Head of School) is a theorist of coherent imaging and relativistic atomic structure. His signature contribution is the theory of X-ray free-electron-laser imaging of single particles, including the modelling of radiation damage and ionisation dynamics during the pulse — the question of whether you can extract structure faster than you destroy it — plus phase-retrieval algorithms for coherent diffractive imaging and ptychography. He also works on relativistic quantum chemistry and atomic structure. Positioned against the established body of NV-ensemble quantum sensing work — DEER, nanoscale NMR and T1 relaxometry protocols operating at pT/sqrt(Hz) field sensitivity — the connection is methodological rather than physical: his group develops the inverse-problem and photon-budget theory that governs how much information can be pulled out of a shot-noise-limited measurement, which is the same limit that fixes pT/sqrt(Hz) performance in NV ensembles. Theory-first PI with strong coupling to experimental synchrotron/XFEL programmes.

van Loock leads theoretical quantum optics and quantum information at Mainz, with a long-standing focus on continuous-variable quantum optics: squeezed and other nonclassical Gaussian states, non-Gaussian resources such as cat and GKP states, hybrid discrete/continuous-variable encodings, and the error-correction and repeater architectures built on them. The group also works on the fundamental limits of quantum-enhanced measurement and on how nonclassical light can be used as a metrological resource. He is theory-first, with output that directly serves the experimental quantum-optics and trapped-ion groups in Mainz. Relative to the established NV-ensemble quantum-sensing playbook (DEER, nanoscale NMR, T1 relaxometry at pT/sqrt(Hz) ensemble sensitivity), the relevance is on the fundamental-light-physics axis rather than the magnetometry axis: this is where the squeezing/nonclassical-state theory sits that would let a spin-ensemble sensor beat the standard quantum limit.