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).

Develops quantum metrology for ultra-weakly-coupled dark sectors and fundamental physics. Directions: (1) axion dark matter detection using entangled probe state preparation and superconducting qubit QND readout (HAYSTAC, ADMX); (2) dark radiation/energy detection with Cooper-pair box quasiparticle sensors; (3) GW detectors based on high-B-field microwave cavities probing early-universe phase transitions; (4) emergent gauge symmetries in quantum spin liquids. Co-PI DARPA QuSeN (quantum sensing of neutrinos, 2025). Devices/Sensors lead, DOE Quantum Science Center.

Specializes in quantum information and hybrid quantum systems. Directions: (1) superconducting qubit quantum computing and error correction; (2) hybrid quantum systems coupling superconducting qubits to mechanical resonators, spin systems, and optical photons; (3) quantum-limited microwave amplification; (4) co-PI DARPA QuSeN — quantum sensing of neutrinos via phonon-coupled SC qubit sensors (2025). Director Pritzker Nanofabrication Facility (PNF). AAAS and APS Fellow.

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.

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.

Croot returned from Princeton to found Sydney's Superconducting Quantum Circuits Laboratory. The programme uses superconducting circuits both as quantum processors and as extremely sensitive probes: coupling microwave resonators and qubits to other degrees of freedom (mechanical modes, semiconductor structures, spins) to build hybrid systems, and developing the quantum-limited amplification chain that makes single-microwave-photon detection possible. 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 — superconducting circuits are the principal competitor technology for detecting the weak microwave signals that NV ensembles read magnetically; a quantum-limited or squeezed microwave amplifier is what lets an inductively-detected spin ensemble reach — and beat — the pT/sqrt(Hz) regime. Newly established, well-equipped lab; high autonomy for a postdoc and active recruitment as the lab builds out.

Explores boundary between condensed-matter physics and quantum sensing using superconductor-semiconductor circuits. Directions: (1) gate-tunable superconductor-semiconductor parametric amplifier for quantum-limited readout (PRA 2023); (2) room-temperature capacitive strong coupling to mechanical motion for electromechanical sensing (Nano Letters 2025); (3) quantum criticality in Josephson junction arrays; (4) synthetic Hamiltonians in hybrid SC-semi devices probing hidden material behavior. IST Austria → Microsoft → JILA → UChicago Nov 2023.

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.

Novotny leads the Photonics Lab with a primary focus on levitodynamics. Research directions: (1) Ground-state cooling of levitated nanoparticles — demonstrated quantum control and motional ground state cooling of silica nanospheres in cryogenic free space (Nature 2021) and all 6 degrees of freedom simultaneously via coherent scattering (Nature Physics 2023); (2) Quantum delocalization and matter-wave interference of levitated nanoparticles (arXiv 2408.01264, 2024); (3) Cavity-mediated long-range interactions between multiple levitated nanoparticles, enabling collective quantum sensing arrays; (4) Optical cold damping, measurement-free coherent feedback (PRL 2025); (5) 2D optoelectronics — graphene/hBN/TMD-based laser detectors and modulators. Heavily cited levitodynamics review (Science 2021, joint with Quidant). Group feeds into applications in quantum-limited force sensing and macroscopic quantum tests.

Eugene Polzik's QUANTOP centre uses hot and ultracold atomic spin ensembles and mechanical membranes to generate squeezed, entangled, and single-photon states for quantum sensing and communication. Key directions include: (1) atomic magnetometry and electromagnetic induction imaging for biomedical applications (MEG/MCG-quality sensors); (2) entanglement between a macroscopic mechanical oscillator and an atomic spin ensemble; (3) quantum memory for light; (4) back-action-evading measurement schemes beyond the SQL; and (5) optical preamplification for MRI. QUANTOP heads the Copenhagen Center for Biomedical Quantum Sensing (CBQS), targeting quantum-enhanced disease diagnostics.