Berengut works on the atomic structure theory underpinning next-generation clocks: highly charged ions, whose optical transitions are both extremely narrow and exceptionally sensitive to variation of fundamental constants and to new physics, and the thorium-229 nuclear clock. He identifies which ionic species and transitions maximise sensitivity to the physics of interest while remaining experimentally accessible, and computes the many-body structure needed to interpret them — work that has directly guided the experimental HCI clock programmes at PTB, MPIK and NIST. 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 — clocks and magnetometers are the two great classes of quantum sensor; his work is on the frequency side of the same estimation problem that fixes pT/sqrt(Hz) performance on the magnetic side. Theory PI with close experimental collaborations.
Byer's long-running program in nonlinear optics and laser physics has produced key technologies for precision measurement, including low-noise laser sources, optical materials, and interferometric techniques that underpin gravitational-wave detectors and frequency metrology.
Chen (PhD, Max Planck Institute of Quantum Optics) develops chip-scale frequency-comb sources for precision metrology and dual-comb spectroscopic sensing, and is now extending integrated thin-film lithium-niobate photonics toward on-chip squeezed-light generation for quantum-enhanced sensing alongside photonic AI accelerators. The lab is actively recruiting postdocs.
Faist is the inventor of the quantum cascade laser (QCL, 1994 at Bell Labs) and leads the Quantum Optoelectronics Group at ETH. Research directions: (1) QCL frequency combs — ring QCLs demonstrate dissipative Kerr solitons in the THz (Science Advances 2023), key for broadband integrated mid-IR spectrometers; (2) Dual-comb spectroscopy — two co-integrated ring QCLs for ultrafast molecular fingerprinting; (3) Quantum cascade detectors — strain-compensated InGaAs/InAlAs QCDs for short-wave mid-IR (<4 µm) sensing; (4) THz strong-coupling — ultrastrongly coupled 2DEG in cavities for quantum photonics; (5) Astrophysical heterodyne receivers — double-metal QCL Josephson mixers. Spin-off: IRsweep (mid-IR dual-comb systems) and Alpes Lasers (QCL commercialisation). FIRST Center head at ETH.
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.
Giessen works on ultrafast nano-optics and plasmonics, plasmonic and metasurface sensors, femtosecond two-photon 3D-printed micro-optics (on fiber tips and detectors), widely tunable ultrafast/mid-IR sources for molecular sensing, and Rydberg-exciton quantum optics in cuprous oxide. In the broader landscape of NV-centre ensemble quantum sensing (DEER, nano-NMR, T1 relaxometry) operating near pT/sqrt(Hz) sensitivity, this work sits adjacent as a nanophotonic sensing and light-source enabler.
Hollberg works on optical atomic clocks, laser frequency stabilization, and frequency-comb metrology, including chip-scale and field-deployable clock technology with applications to relativistic geodesy and precision tests of fundamental physics.
Siddarth Joshi's group works on satellite-based quantum key distribution, quantum information protocols, and chip-scale quantum technologies. Research: (1) QKD receiver miniaturization for satellites and CubeSats; (2) chip-scale quantum random number generation and single-photon detection; (3) quantum metrology and sensing with photonic chips. Part of EPSRC Quantum Communications Hub.
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.
Kippenberg leads the Laboratory of Photonics and Quantum Measurements (K-Lab) at EPFL, pioneer of chip-scale microresonator frequency combs and cavity optomechanics. Research directions: (1) Soliton microcombs — dissipative Kerr solitons in Si3N4 microresonators for massively parallel coherent optical communications, precision ranging/LiDAR (Science 2018, Nature 2017); dual-chirped microcomb parallel ranging at megapixel rates; (2) Room-temperature quantum optomechanics — phononic-crystal-patterned Si3N4 membrane-in-the-middle cavity reduces frequency noise 700×, observing quantum backaction at room temperature (Nature 2024); (3) Superconducting circuit optomechanics — topological lattices, electromechanical sensing (Nature 2022); (4) Free-electron–photon interactions in microresonators. Spin-off companies and strong industry ties. Over 85,000 citations, h-index ~80.