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).
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 — ultra-sensitive force/acceleration sensing, directional dark matter detection with levitated sensors; (3) Meta-atom levitation — Mie-resonance high-permittivity particles in optical traps for extreme light-matter interaction; (4) Optofluidics — structured light for photothermal fluid control; (5) Cancer phototherapy — photothermal nanoparticle applications. Pioneer in nanoplasmonic tweezers, thermoplasmonics, and on-chip biosensing. Key co-author of Science levitodynamics review (2021).
Hendrik Ulbricht's group pioneers levitated optomechanics and macroscopic quantum systems. Research: (1) optical levitation of nanoparticles for zeptonewton force sensing and quantum-to-classical transition tests; (2) magnetic levitation of micromagnets (diamagnetically stabilised) as ultralight dark matter detectors and magnetometers (fT/√Hz sensitivity demonstrated with LeMaMa levitated ferromagnet); (3) spin entanglement witness for quantum gravity (BMV experiment — levitated diamond with NV centre); (4) tests of the Diósi-Penrose model of wavefunction collapse. Multiple Reviews of Modern Physics; active in macroscopic quantum physics community.
Vijayan leads the Quantum Engineering Lab at Manchester's Photon Science Institute, focusing on levitated optomechanics. Key results: (1) Programmable cavity-mediated long-range interactions between two levitated nanoparticles via coherently scattered photons (Nature Physics 2024, ETH Zurich/Innsbruck collaboration before Manchester); (2) Ground-state cooling of nanospheres and building toward quantum superpositions; (3) Quantum sensing with levitated systems — ultra-sensitive force/acceleration detectors; dark matter searches with nanoparticle momentum transfer detection (QTFP-funded collaboration with Darren Price); (4) Multi-particle quantum arrays. Royal Society University Research Fellow. Currently advertising PhD positions in quantum sensing with levitated optomechanical systems. Collaborates with Novotny (ETH), Romero-Isart (Innsbruck), and Millen (King's College London).