Crozier holds a joint Physics/Electrical Engineering chair and runs a nanophotonics laboratory spanning plasmonic and dielectric metasurfaces, on-chip optical trapping and manipulation of nanoparticles and cells, mid-infrared spectroscopy and detection with metasurface-enhanced and colloidal-nanocrystal devices, and light emission from 2D semiconductors. The unifying theme is engineering the local optical density of states to increase the signal available from a very small number of emitters or molecules. 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 — the plasmonic and dielectric antenna work is the same physics used to raise photon collection efficiency and hence the shot-noise floor of NV-ensemble magnetometers operating at pT/sqrt(Hz). Note: a substantial fraction of the group's output is device fabrication rather than sensitivity-limited measurement, which is a caveat against the stated preference.
Faist is the inventor of the quantum cascade laser (QCL, 1994 at Bell Labs) and leads the Quantum Optoelectronics Group at ETH. Research directions: (1) QCL frequency combs — ring QCLs demonstrate dissipative Kerr solitons in the THz (Science Advances 2023), key for broadband integrated mid-IR spectrometers; (2) Dual-comb spectroscopy — two co-integrated ring QCLs for ultrafast molecular fingerprinting; (3) Quantum cascade detectors — strain-compensated InGaAs/InAlAs QCDs for short-wave mid-IR (<4 µm) sensing; (4) THz strong-coupling — ultrastrongly coupled 2DEG in cavities for quantum photonics; (5) Astrophysical heterodyne receivers — double-metal QCL Josephson mixers. Spin-off: IRsweep (mid-IR dual-comb systems) and Alpes Lasers (QCL commercialisation). FIRST Center head at ETH.
Wysocki develops quantum-cascade-laser-based spectroscopic sensing systems, including external-cavity QCLs, dispersion spectroscopy, and mid-IR dual-comb spectrometers, that routinely reach fundamental quantum-noise detection limits for trace-gas sensing; applications span atmospheric/environmental monitoring, drone-based methane leak detection, industrial process control, and human breath-based metabolic/medical diagnostics.