Description: Production and characterization of non-classical states of light (squeezed, twin-beam) in optical fiber and waveguide platforms.
Parigi co-leads the Multimode Quantum Optics group at LKB alongside Treps. Research directions: (1) Multimode squeezed-state quantum networks β generating large-scale entangled cluster states using optical frequency combs; reconfigurable graph-state topologies for measurement-based quantum computing and distributed quantum sensing; (2) Multimode quantum sensing β using multimode squeezed states for simultaneous beyond-shot-noise estimation of multiple parameters (wavelengths, phases) in a spectrometer; (3) Non-Gaussian quantum states β heralded subtraction and addition of photons to Gaussian cluster states for universal CV quantum computation; (4) Quantum networks at telecom β generating multimode squeezed states compatible with fiber transmission. ERC Laureate. Employed by Sorbonne UniversitΓ©.
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.
John Rarity's group works on quantum-enhanced measurements and free-space quantum key distribution. Research: (1) quantum imaging with undetected photons β mid-infrared gas sensing (CO2, CH4) exploiting entangled photon pairs, with only near-IR photons detected (startup QLM); (2) sub-shot-noise imaging using quantum-identical photon beams; (3) spin-photon interfaces (1D cavity with near-unit scattering efficiency); (4) compact satellite QKD transmitters (EPSRC Quantum Comms Hub). Highly relevant to quantum-enhanced sensing.
Prof. Shahriar's group uses atomic and optical systems for precision measurement and quantum information. Key directions: (1) White-light cavities β using anomalous dispersion media inside optical cavities to create a bandwidth-extended cavity enabling broadband gravitational wave detector sensitivity enhancement beyond current LIGO designs; (2) Superluminal (fast-light) gyroscopes β anomalous-dispersion-enhanced ring-laser gyroscopes for measuring the Lense-Thirring frame-dragging effect as a test of general relativity, with >10βΆΓ sensitivity enhancement over conventional Sagnac gyroscopes; (3) Quantum memories and computers using trapped atomic ensembles (PRISM protocol); (4) Ultra-low-light nonlinear optics with nanofibers and atoms for optical switching and quantum logic; (5) Holographic and polarimetric image processing. Member of LIGO Scientific Collaboration; contributed to GW170817 binary neutron star merger discovery. AT&T Professor of ECE.
Treps leads the Multimode Quantum Optics group at LKB. Research directions: (1) Multimode quantum frequency combs β synchronously pumped OPO (SPOPO) generates entangled networks of squeezed modes with configurable graph structure; first demonstration of quantum frequency comb with multimode squeezing (PRL 2012); (2) Quantum-enhanced multiparameter estimation β quantum Fisher information and multimode squeezing for simultaneous beyond-shot-noise parameter estimation (e.g., frequency comb spectral centroid and energy, PRX 2020); (3) Non-Gaussian quantum states β heralded generation of non-Gaussian cluster states for CV quantum computing; (4) Quantum metrological inequalities β relating non-locality to parameter estimation. Spin-off: Cailabs (multimode fiber light-shaping for telecom and industrial lasers). Co-director of QICS. ERC-funded.
Nicolas Treps' multimode quantum optics group (with Valentina Parigi and Claude Fabre) generates and characterises highly multimode squeezed and entangled states of light. Research: (1) optical frequency combs as multimode squeezed state resources β quantum metrology and sensing with frequency combs; (2) reconfigurable multimode squeezed state networks for quantum computing and sensing; (3) spatiotemporal squeezing with optical parametric amplifiers. Key for quantum-enhanced sensing with light.
Xu works on frequency-dependent squeezed-light injection for quantum-enhanced gravitational-wave detection at LIGO and on trapped-cavity atom interferometry for precision tests of fundamental physics, bridging quantum optics and atom-based inertial sensing.