Spin Dynamics of Molecules “Standing” on Metal Surfaces

Nanoscale control of atomic assemblies is central to the miniaturization of spintronic devices. Atom manipulation with Scanning Tunneling Microscopy (STM) provides the possibility to construct well-defined structures on surfaces. Electron Spin Resonance (ESR) using STM has established itself as the workhorse for studies of individual spins on surfaces. Up until now, ESR-STM was bound to insulating layer, limiting this technique to a small range of problems in chemistry and physics. In this work, we demonstrate that an organic molecule, can be used as a mobile ESR-based quantum sensor on the tip, with sensitivity to electrostatic and magnetic fields with atomic scale resolution.