Aeppli leads the Quantum Technologies Group spanning ETH Zurich, EPFL, and PSI. Research directions: (1) Quantum materials imaging — using SLS synchrotron X-rays (including SwissFEL ultrafast pulses) and neutrons at SINQ to image quantum phase transitions, skyrmions, and correlated phases; non-destructive imaging of device structures; (2) Rare-earth quantum magnets and qubits — LiHoF4 as a model quantum system; Er, Pr, and Nd spin qubits in crystals for quantum information and sensing; (3) Semiconductor quantum devices — silicon and germanium nanostructures probed by synchrotron nanoscale X-ray imaging; (4) Van der Waals materials and CDW memory devices. Strong interface with PSI large-scale facilities as unique quantum sensing tools for materials.

Klein pairs van der Waals heterostructure fabrication with a cryogenic scanning-probe 'Atomic Single Electron Transistor,' built on a quantum-twisting-microscope platform, to directly image sub-moire electrostatic potential landscapes with ultrasensitive, high-spatial-resolution electrometry. This is an unpreferred/borderline quantum-sensing inclusion: the sensor is an SET-based electrometer rather than an NV-ensemble magnetometer (which reaches pT/sqrt(Hz) via DEER/NMR/T1 protocols), but it shares the goal of pushing single-defect-level sensitivity for imaging quantum materials.

Kobus Kuipers' lab develops and applies near-field optical microscopy to study nanophotonic phenomena with sub-wavelength spatial resolution. Research: (1) near-field imaging of topological photonic states (topological edge and interface modes in photonic crystals); (2) near-field microscopy of plasmonics and nanophotonics; (3) visualizing light transport at the nanoscale. Borderline for quantum sensing but directly relevant to nanophotonic quantum sensing platforms.

Loth combines ESR-STM with ultrafast terahertz-driven STM to read out and control individual atomic and molecular spins with atomic spatial and picosecond temporal resolution - single-spin quantum sensing at the ultimate spatial limit. In the broader landscape of NV-centre ensemble quantum sensing (DEER, nano-NMR, T1 relaxometry) operating near pT/sqrt(Hz) sensitivity, this work pushes spin sensing to the single-atom, ultrafast regime.

Otte's group pioneered electron-spin-resonance scanning tunneling microscopy (ESR-STM), positioning individual atoms one-by-one with a low-temperature STM tip and using all-electrical RF driving to coherently control and single-shot read out individual electron and nuclear spins (e.g., single 49Ti nuclei) with sub-neV energy resolution and atomic spatial resolution. Where NV-ensemble sensing reaches pT/sqrt(Hz) at the nanoscale, Otte's ESR-STM instead reaches the ultimate single-atom limit of magnetic sensing and quantum control, and the lab is developing a next-generation 15 T / 20 mK STM to push coherence times and energy resolution further.

Rogge (formerly Delft) works on the spectroscopy of individual dopant atoms in silicon: using transport, STM and microwave spectroscopy to read out the orbital, valley and spin structure of single donors and acceptors, including their coupling to strain, electric fields and each other. The group has mapped the wavefunctions of individual dopants and used acceptor spin-orbit coupling for electric-field-driven spin control. This is single-quantum-object measurement rather than device engineering. 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 — single-donor spectroscopy is the silicon analogue of single-NV work: the same questions about coherence, bath engineering and readout fidelity that fix pT/sqrt(Hz) ensemble performance appear here in a platform where the sensor can be placed with atomic precision and interrogated electrically rather than optically.

Simmons pioneered atomic-precision fabrication in silicon: hydrogen-resist STM lithography, phosphine dosing and epitaxial silicon overgrowth to place individual dopant atoms with sub-nanometre accuracy, then measure them at millikelvin. The programme has produced single-atom transistors, precision dopant arrays used as analogue quantum simulators, and the largest atom-scale device platform in the world; she also founded Silicon Quantum Computing Pty Ltd. The sensing-relevant capability is the single-electron transistor as an exquisitely sensitive electrometer, capable of resolving individual charge transitions and mapping local electrostatic potential at the atomic scale. 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 — her SET electrometry is the charge-domain counterpart to magnetic NV sensing at pT/sqrt(Hz): both are single-quantum-object detectors whose performance is limited by back-action and by the noise of the readout chain. Very large group, strongly fabrication-oriented and commercially entangled, which cuts against the stated preference for sensitivity-limited rather than fabrication-limited work.