De Sterke is a theorist-experimentalist of nonlinear and structured photonics. The group's signature recent contribution is the pure-quartic soliton: by engineering the dispersion of a waveguide so that the group velocity depends on the third power of frequency, they produce solitons with a different energy-width scaling from conventional ones, with direct consequences for mode-locked laser and frequency-comb design. The group also works on topological and non-Hermitian photonics and on THz metamaterials. 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 relevance is to the light side of the search rather than the spin side: dispersion-engineered comb and soliton sources are the local oscillators and reference clocks that any optical readout of a pT/sqrt(Hz) sensor ultimately depends on. Borderline inclusion; kept for the fundamental-light-physics criterion.

Eggleton directs the Institute of Photonics and Optical Science and runs one of the world's leading groups on stimulated Brillouin scattering in integrated photonic circuits — the coherent interaction of light with GHz acoustic phonons in a chalcogenide or silicon waveguide. The consequences are a chip-scale microwave photonic toolbox (ultra-narrowband filters, true time delay, RF spectral analysis), photon-phonon memory, and, through the Jericho Smart Sensing Laboratory, translation into deployed sensing platforms. 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 — Brillouin optomechanics is a distinct route to the same goal — reading a weak signal out of a high-Q, low-loss resonator at the quantum noise floor — and the group's phonon-photon coupling is strong enough that quantum optomechanical operation is now within reach. Very large, very well-resourced group with extensive industry and defence funding; a candidate would be one of many.

Fleming pioneered microstructured polymer optical fibre and continues to work on specialty fibre fabrication: drawing exotic polymer, hybrid polymer-metal and poled-silicate structures that would be impossible in conventional silica, and using them to build metamaterials and biomedical photonic devices including fibre-based sensors and probes. The fabrication route — preform drawing — gives access to geometries and material combinations that lithography cannot reach. 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 relevance to a sensing postdoc is delivery and packaging: fibre-integrated probes are the standard way to get an NV or vapour-cell sensor into a biological or field environment while preserving its pT/sqrt(Hz) sensitivity. Borderline inclusion; senior PI, fabrication-led.

Kuhlmey works on structured electromagnetic materials across an unusually wide frequency range: microstructured optical fibres, metamaterials, non-reciprocal and time-varying media, and — the newest and most sensing-relevant thread — quantum terahertz photonics, in collaboration with ENS Paris and CSIRO. The THz programme is explicitly aimed at single-photon/single-electron coupling in the THz band, which if it works would allow quantum devices to operate at a few kelvin rather than millikelvin. The group runs a THz time-domain spectroscopy lab with cryogenic capability. 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 THz band is the one part of the spectrum where neither superconducting circuits nor NV ensembles currently offer quantum-limited detection, so this is a genuine gap-filling programme rather than a variation on existing pT/sqrt(Hz) approaches.

Merklein is the independent PI within the Eggleton group most focused on the acoustic side of Brillouin physics: he demonstrated on-chip photon-phonon memory (coherently transferring an optical pulse into a long-lived acoustic excitation and back), and works on distributed Brillouin sensing in optical fibre and on the coherent control of travelling acoustic waves in waveguides. The distributed-sensing thread is a practical, sensitivity-limited measurement problem: recovering strain and temperature along kilometres of fibre from a very weak backscattered signal. 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 — phonon-mediated storage and readout is a complementary transduction channel to spin-based sensing, and the group is now pushing toward the quantum regime where the acoustic mode must be treated as a quantum object rather than a classical one. Early-career PI (DECRA) with genuine independence inside a large group.