Caldwell is a Royal Society University Research Fellow establishing the Molecular Quantum Matter Lab at UCL. Research directions: (1) Precision molecular spectroscopy for dark matter and fifth-force searches — measuring isotope shifts in molecular systems to test Standard Model predictions and probe new forces between neutrons and electrons; (2) Quantum control of molecules in external fields — laser cooling, Stark deceleration, and magneto-optical trapping of polar molecules; (3) Molecular beam spectroscopy with frequency comb referencing for ultra-high-precision lineshape measurements. The lab aims to build the most precise molecular spectrometer for BSM physics searches. Actively building the lab and seeking motivated students/postdocs.
Flambaum is one of the most cited atomic theorists alive and the intellectual source of a large fraction of the modern precision-AMO new-physics programme. His group computes the atomic and molecular structure factors that convert an experimental frequency shift into a bound on new physics: enhancement factors for electron and nuclear EDMs, atomic parity violation, the sensitivity of clock transitions to variation of the fine-structure constant, and — most relevant to quantum sensing — the response of atomic clocks, magnetometers and comagnetometers to ultralight/axion-like dark matter fields. He proposed much of the theory behind using networks of quantum sensors as dark matter detectors. 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 — his theory is what tells an experimentalist what a pT/sqrt(Hz) magnetometer or a 10^-18 clock actually constrains: without it, a spin-precession measurement is just a number. Theory group; a sensing postdoc would collaborate rather than join.
Jean-Philippe Karr's trapped-ions group at LKB performs precision spectroscopy of molecular ions (HD+, H2+) to test quantum electrodynamics and determine fundamental constants. Research: (1) laser spectroscopy of HD+ molecular ions in ion traps for proton-electron mass ratio determination; (2) tests of quantum electrodynamics in simple molecular systems; (3) search for physics beyond the standard model via precision measurement. Published in Physics (April 2026) on simplest molecules testing quantum theory.