Description: Pulsed radiation-pressure interactions for back-action-evading position measurement, mechanical state squeezing, and quantum state tomography of nano/micromechanical resonators.
Barker leads the UCL Optomechanics Group, focusing on levitated nano/micro-oscillators in vacuum. Research directions: (1) Six-degree-of-freedom cooling โ 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 โ 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).
Tulio Brito Brasil focuses on multimode quantum optics, squeezed and entangled states of light, and their application for quantum sensing and communication. Research: (1) generation of two-colour high-purity EPR photonic states; (2) squeezed light for quantum noise reduction in measurement; (3) continuous variable quantum optics protocols for networks. Recently joined QUANTOP at NBI.
Pierre-Franรงois 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 โ 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) โ early demonstration of radiation-pressure back-action in a micro-mirror (Nature 2006), subsequent beating of SQL via quantum correlations; (2) Micro/nanomechanical resonators โ 2D photonic crystal deformable slabs, membrane-in-the-middle cavities, micropillar resonators for radiation-pressure optomechanics; (3) Superconducting qubitโmacroscopic membrane coupling โ Jacqmin & Delรฉglise 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 โ VIRGO/LIGO data analysis and quantum noise modeling. Applications include back-action-evading force sensing and tests of quantum mechanics at macroscopic scales.
Ivette Fuentes' group uses quantum information and metrology to probe fundamental physics at the interface of quantum theory and general relativity. Research: (1) quantum sensing of gravitational waves using relativistic quantum systems; (2) quantum clock synchronization and gravitational decoherence; (3) dark energy detection using quantum sensors; (4) quantum reference frames in curved spacetime. Bridges quantum sensing with gravitational physics.
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 โ 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 โ phononic-crystal-patterned Si3N4 membrane-in-the-middle cavity reduces frequency noise 700ร, observing quantum backaction at room temperature (Nature 2024); (3) Superconducting circuit optomechanics โ topological lattices, electromechanical sensing (Nature 2022); (4) Free-electronโphoton interactions in microresonators. Spin-off companies and strong industry ties. Over 85,000 citations, h-index ~80.
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.
Quidant leads the Nanophotonic Systems Laboratory, developing hybrid integrated levitation platforms combining optical and RF fields. Research directions: (1) Measurement-free coherent optical feedback cooling of levitated nanoparticles (PRL 2025, phonon occupations ~100s); (2) Quantum sensing applications โ ultra-sensitive force/acceleration sensing, directional dark matter detection with levitated sensors; (3) Meta-atom levitation โ Mie-resonance high-permittivity particles in optical traps for extreme light-matter interaction; (4) Optofluidics โ structured light for photothermal fluid control; (5) Cancer phototherapy โ photothermal nanoparticle applications. Pioneer in nanoplasmonic tweezers, thermoplasmonics, and on-chip biosensing. Key co-author of Science levitodynamics review (2021).
Massimiliano Rossi's lab focuses on levitated systems, optical tweezers, and quantum measurement. Research: (1) optically levitated nanoparticles for force sensing and zeptonewton-scale measurements; (2) quantum measurement and control of levitated systems approaching the quantum ground state; (3) back-action-evading measurement schemes for levitated oscillators; (4) exploring quantum-to-classical transitions. The lab is developing levitated systems as sensors for dark matter and gravitational waves.
Vanner leads the Quantum Measurement Lab, combining experiment and theory. Key research areas: (1) Cavity quantum optomechanics โ developed a theoretical framework capturing nonlinear radiation-pressure beyond the linearised approximation, showing deterministic mechanical Wigner-negativity generation; demonstrated mechanical position-squared measurements in Nature Comms (2016); thermal noise squeezing by 36 dB (Nat. Comms 2013); (2) Brillouin-Mandelstam scattering โ demonstrated strong coupling to high-frequency phonons (Optica 2019); single-phonon addition/subtraction via Brillouin (PRL 2021); quantum state tomography with non-Gaussianity; (3) Hybrid quantum systems โ 'displacemon' architecture (nanobeam magnetically coupled to superconducting qubit, PRX 2018) for testing objective collapse and dark matter; (4) Quantum gravity tests โ proposals for testing the generalised uncertainty principle (GUP) using optomechanical protocols. UKRI QTFP fellowship.