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.