Barker leads the UCL Optomechanics Group, focusing on levitated nano/micro-oscillators in vacuum. Research directions: (1) Six-degree-of-freedom cooling — demonstrated simultaneous cavity cooling of all 6 DOF of a levitated nanoparticle (Nature Physics 2023, with Monteiro); (2) Sympathetic cooling of two nanoparticles via Coulomb interaction, squeezing transfer (Phys. Rev. Research 2023); (3) Dark matter searches — levitated nanoparticles as directional dark matter sensors sensitive to nuclear recoil and momentum transfer; QTFP-funded project 'Development of Levitated Quantum Optomechanical Sensors for Dark Matter Detection'; (4) Controlling mode orientations for directional force sensing near the quantum limit; (5) Quantum macroscopic superposition tests. Closely collaborates with Monteiro (theory), Bose (quantum entanglement tests), and Ghag (dark matter).
Briant works in LKB's optomechanics and quantum-measurement team, using high-finesse Fabry-Perot cavities coupled to mirror/membrane mechanical resonators to study radiation-pressure back-action, quantum noise, and force sensing near the standard quantum limit, alongside Pierre-Francois Cohadon and Antoine Heidmann.
Cohadon and Heidmann co-lead the Optomechanics and Quantum Measurements group at LKB. Research directions: (1) Back-action evasion and Standard Quantum Limit (SQL) — early demonstration of radiation-pressure back-action in a micro-mirror (Nature 2006), subsequent beating of SQL via quantum correlations; (2) Micro/nanomechanical resonators — 2D photonic crystal deformable slabs, membrane-in-the-middle cavities, micropillar resonators for radiation-pressure optomechanics; (3) Superconducting qubit–macroscopic membrane coupling — Jacqmin & Deléglise team: resonant coupling of transmon qubit to MHz membrane oscillator, tracking quantum motion with 300 repeated interactions (2025); high-impedance hyperinductors for electromechanics; (4) Gravitational wave detector contributions — VIRGO/LIGO data analysis and quantum noise modeling. Applications include back-action-evading force sensing and tests of quantum mechanics at macroscopic scales.
Pierre-François Cohadon leads the optomechanics and quantum measurements group at LKB (ENS site). Research: (1) mechanical quantum systems and back-action-evading measurement; (2) gravitational wave detector enhancement — white-light cavity proposals to extend GW sensitivity; (3) quantum optomechanical sensing of forces and fields. The group was key to the LKB optomechanics tradition and is affiliated with Virgo/LIGO enhancement proposals.
Courty provides theoretical support to LKB's optomechanics and quantum-measurement experiments, working on quantum-noise theory for radiation-pressure coupled cavities and standard-quantum-limit-evading measurement schemes.
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.
Guerlin works on quantum-limited optomechanical measurement and quantum non-demolition detection schemes within LKB's optomechanics team, building on cavity-QED-style quantum-measurement concepts applied to mechanical degrees of freedom.
Heidmann is a founding member of LKB's cavity-optomechanics group, whose work on radiation-pressure effects, ponderomotive squeezing, and quantum-limited displacement/force measurement underpins the lab's broader precision-metrology and gravitational-wave-adjacent quantum-optics programme.
Hong runs Hybrid Optical Quantum Technologies within Stuttgart's FMQ institute: optomechanical and opto-mechanical-spin hybrid devices used for quantum sensing and for tests of quantum mechanics at larger mass scales. Work covers cavity/phononic-crystal optomechanics driven toward the quantum regime (ground-state cooling, back-action-evading and quantum-limited displacement/force readout) and the coupling of diamond spin defects to mechanical motion, including levitated-diamond spin-mechanics -- where an NV inside a levitated particle both senses and controls the particle's motion. Relative to the established NV-ensemble quantum-sensing playbook (DEER, nanoscale NMR, T1 relaxometry at pT/sqrt(Hz) ensemble sensitivity), this is the same colour-centre physics, deliberately hybridized with mechanics: the sensing target shifts from magnetic field to force, acceleration and displacement, and the group sits alongside Wrachtrup's NV programme in the same building, which is a considerable practical advantage.
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.