The de Leon lab engineers nitrogen-vacancy and other color centers in diamond and wide-bandgap materials as solid-state quantum sensors and qubits, spanning materials growth and surface chemistry, nanophotonic integration, and magnetic-field/thermal sensing of quantum materials, alongside a parallel effort on superconducting qubit noise and loss. This builds on the broader tradition of ensemble NV magnetometry (DEER, NMR, T1 relaxometry) that has reached pT/sqrt(Hz)-class sensitivities, which de Leon's group extends toward single- and few-spin scanning-probe magnetometry of correlated electron materials.
Degen leads the Spin Physics and Imaging group, one of the world's leading NV-center magnetometry labs. Research directions (as of 2025): (1) Scanning NV magnetometry of quantum materials — NV-tipped cantilevers image current flow (≲50 nm resolution) in graphene heterostructures and resolve domain walls in antiferromagnets/ferroelectrics; cryogenic scanning down to 350 mK in dilution refrigerator (published Appl. Phys. Lett. 2022). (2) Single-molecule NMR — shallow NV centers detect nuclear spins from surface-adsorbed molecules with sub-nanometer 3D resolution; 2022 Nano Lett. on amine-functionalized diamond surfaces; exploring chirality-induced spin selectivity at few-molecule level. (3) NV magnetometry protocols — reconstruction-free waveform sensing (1.1 ns time resolution, Nature 2025), gradiometric detection, spectrum demodulation for rapid scanning, multi-NV addressing. (4) Diamond nanoengineering — multicone pillar waveguides, surface engineering, scanning probe fabrication. ERC Proof-of-Concept 2025 for photonic IC single-photon NV excitation/detection for commercial quantum sensing.
Hemmer pioneered NV-diamond spin sensing and super-resolution with spin defects, working on coherent control, photonic integration of NV sensors, and diamond-based magnetometry/imaging bridging physics and engineering. In the broader landscape of NV-centre ensemble quantum sensing (DEER, nano-NMR, T1 relaxometry) operating near pT/sqrt(Hz) sensitivity, this work is directly in the NV ensemble sensing lineage, emphasizing photonic integration and super-resolution readout.
Jacques is a pioneer of scanning NV magnetometry, using single nitrogen-vacancy spins in scanning-probe diamond tips to image magnetic textures at the nanoscale under ambient conditions. His team applies this to condensed-matter systems including antiferromagnetic domain walls and chiral spin textures, non-collinear antiferromagnetic order via single-spin relaxometry, and current-driven skyrmion motion in synthetic antiferromagnets, work carried out in close collaboration with materials-physics groups.
Wrachtrup is a founder of NV-centre quantum sensing: single-spin and ensemble magnetometry, nanoscale/single-molecule NMR and ESR, nuclear-spin registers, scanning-probe quantum-materials imaging, and programmable diamond nanosensors for chemistry and biology. His group actively recruits postdocs across NV sensing and quantum technology. In the broader landscape of NV-centre ensemble quantum sensing (DEER, nano-NMR, T1 relaxometry) operating near pT/sqrt(Hz) sensitivity, this work is the reference point, extending DEER/nano-NMR toward single-molecule and cryogenic regimes.