Technique - (26) Resonance fluorescence / quantum light spectroscopy

Type: Experimental

Description: Coherent excitation of single emitters (quantum dots, atomic vapour) to study quantum optical phenomena such as photon antibunching, resonance fluorescence, and non-classical light generation.

Department(s)/lab(s): Physics (Atomic and Laser Physics Sub-department) | Atom-Photon Connection Group @ Oxford
Summary:

Kuhn leads the Atom-Photon Connection group, working at the single-atom, single-photon level. Key research thrusts: (1) deterministic generation of indistinguishable single photons from single atoms in high-finesse cavities, with cluster-state production for one-way quantum computing; (2) development of integrated fibre-tip microcavities with small radius-of-curvature for >50% photon capture efficiency and direct fibre coupling; (3) single-photon quantum memories using cavity-coupled atom systems; and (4) optical trapping of single atoms in the Lamb-Dicke regime for quantum simulation and networking. The group uses reinforcement learning for optimal quantum control of atom-cavity systems.

Department(s)/lab(s): Physics / Electrical and Computer Engineering | Kwiat Quantum Optics Group @ UIUC
Summary:

Pioneer of experimental quantum optics with entangled and hyper-entangled photons; research spans quantum information processing, quantum communication, quantum-enhanced metrology and sensing, and fundamental tests of quantum mechanics using single- and entangled-photon sources.

Department(s)/lab(s): Physics / QET Labs | Laing Group (Bristol QET Labs) @ Bristol
Summary:

Anthony Laing's group pioneers photonic quantum computing and quantum simulation, having invented integrated quantum photonics. Research: (1) universal reconfigurable photonic quantum processors; (2) photonic quantum simulation for chemistry and materials science; (3) photonic quantum sensing using multi-photon interference on chip. Founded PsiQuantum co-founder and Quantum in the Summer school.

Department(s)/lab(s): Physics / Niels Bohr Institute | Quantum Photonics Group (Lodahl Lab) @ UCPH
Summary:

Peter Lodahl's Quantum Photonics Group develops deterministic photon-emitter interfaces using semiconductor quantum dots embedded in photonic nanostructures (nanowires, photonic crystal waveguides). Research targets: single-photon sources with near-unity efficiency and indistinguishability; spin-photon interfaces for quantum repeaters; integrated quantum photonic circuits; and quantum networks based on single emitters. The group leads the Hy-Q Centre for Hybrid Quantum Networks and holds several quantum technology patents and spin-out companies. Borderline case — primarily quantum photonics for networking but with quantum sensing applications (single photon sensing, spin-photon).

Department(s)/lab(s): Physics | Institute of Semiconductor Optics and Functional Interfaces (IHFG) @ Stuttgart
Summary:

Michler's IHFG grows and studies semiconductor quantum dots as on-demand single- and entangled-photon sources, including telecom-band emitters, on-chip Hanbury-Brown-Twiss/photonic integration, and atom-QD hybrid interfaces - core fundamental-light and quantum-photonic-sensing resources. Cleanroom epitaxy on site. In the broader landscape of NV-centre ensemble quantum sensing (DEER, nano-NMR, T1 relaxometry) operating near pT/sqrt(Hz) sensitivity, this work supplies nonclassical light sources that can enhance optical sensing.

Department(s)/lab(s): Physics – Institute for Quantum Electronics | Nanoscale Quantum Optics Group (Murthy) @ ETH Zurich
Summary:

Murthy leads the Nanoscale Quantum Optics group at ETH, studying light-matter interactions in nanostructures to engineer novel quantum states of light. Research directions: (1) Photon-photon interactions — achieving strong effective photon-photon interactions via coupling to quantum emitters in 2D materials and optical nanocavities; exploring photonic Mott insulators and collective quantum phases of light; (2) 2D semiconductor quantum emitters — localized excitons in TMD heterostructures as sources of single photons and entangled photon pairs; (3) Quantum light from cavities — engineering photon statistics and squeezing using cavity-QED with 2D materials; (4) Ultrafast quantum optics — attosecond-scale probing of light-matter entanglement. New group as of ~2023.

Department(s)/lab(s): Physics / QET Labs | Oulton Group @ Bristol
Summary:

Ruth Oulton's group works on quantum photonics using solid-state single-photon emitters. Research: (1) semiconductor quantum dot single-photon sources — cavity-enhanced emission, photonic crystal integration; (2) hBN defect spin-photon interfaces; (3) integrated quantum photonics for sensing and quantum networks. The group focuses on device-quality semiconductor photonic systems for quantum information and sensing applications.

Department(s)/lab(s): Physics / Niels Bohr Institute | Quantum Photonics Group (Lodahl/Paesani) @ UCPH
Summary:

Stefano Paesani works on photonic quantum information processing and quantum sensing. Research: (1) silicon quantum photonic integrated circuits for quantum computing and measurement; (2) boson sampling and quantum advantage with photons; (3) quantum sensing using photonic cluster states. Recently joined Lodahl group at NBI as associate professor.

Department(s)/lab(s): Physics and Astronomy | Quantum Nanophotonics Group (Politi) @ Southampton
Summary:

Alberto Politi's Quantum nanoPhotonics Lab develops photonic quantum technology platforms for quantum information and sensing. Research: (1) integrated quantum photonic circuits in silicon, glass, and diamond; (2) quantum simulation with integrated photonics; (3) single-photon sources coupled to nanophotonic waveguides (including hBN defect emitters). Part of UK Quantum Technology Hubs.

Department(s)/lab(s): Electrical Engineering / Physics / QET Labs | Rarity Group @ Bristol
Summary:

John Rarity's group works on quantum-enhanced measurements and free-space quantum key distribution. Research: (1) quantum imaging with undetected photons — 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.