Technique - (3) Scanning probe magneto-optical Kerr / XMCD spectroscopy

Type: Experimental

Description: Spatially resolved magneto-optical Kerr imaging and synchrotron XMCD for element-specific spin and orbital magnetometry with sub-micron resolution.

Department(s)/lab(s): Physics – Laboratory for Solid State Physics (ETH) / PSI / EPFL | Quantum Technologies Group (Aeppli, ETH/PSI/EPFL) @ ETH Zurich
Summary:

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.

Department(s)/lab(s): Department of Materials (D-MATL) | Magnetism and Interface Physics Group (Gambardella) @ ETH Zurich
Summary:

Gambardella leads the Magnetism and Interface Physics group at ETH D-MATL. Research directions: (1) Scanning probe magnetometry — using NV-center cantilevers (collaboration with Degen) and magneto-optical Kerr microscopy to image spin textures (skyrmions, domain walls) in thin-film heterostructures with sub-100 nm resolution; (2) Spin-orbit torques — current-induced magnetization switching via interfacial spin-orbit coupling; spin Hall and Rashba effects for spintronic devices; (3) Single-atom magnetism — STM and X-ray absorption for element-specific orbital and spin moments of individual atoms on surfaces; (4) XMCD at synchrotron — quantitative element-specific magnetic spectroscopy. Quantum sensing angle: spin-orbit driven phenomena, high-resolution magnetic imaging.

Department(s)/lab(s): Physics | Yacoby Lab @ Harvard
Summary:

Yacoby's lab develops scanning-probe quantum sensors, most notably scanning single-NV-center magnetometers and SQUID-on-tip probes, to image nanoscale magnetic textures and current flow in quantum materials at cryogenic and millikelvin temperatures. This scanning-probe approach extends the sensitivity and spatial resolution of NV ensemble quantum sensing experiments (DEER, nanoscale NMR, T1 relaxometry), which established pT/√Hz-class magnetometry, down to single-spin, nanometer-scale imaging of individual quantum materials.