New Scanning Probes for Nanomagnetic Imaging

I will discuss recent experiments in our group aimed at developing and applying two promising new magnetic scanning probes.

The first probe is based on newly developed nanowire (NW) force sensors, which have recently enabled a form of AFM capable of mapping both the size and direction of tip-sample forces.  I will present first results in which we functionalize such NWs with nanometer-scale magnetic tip and characterize their behavior.  Using these NW sensors, we intend to realize a form of vectorial MFM capable of mapping stray magnetic fields with enhanced sensitivity and resolution compared to the state of the art.
The second scanning probe consists of a sharp quartz tip with a nanometer-scale superconducting quantum interference device (SQUID) integrated on its end.  This SQUID-on-tip (SOT) sensor achieves record sensitivity to both stray magnetic flux and local thermal dissipation. I will discuss experiments using this device to map the stray magnetic field produced by individual nanomagnets and superconducting vortices.
The unique capabilities of both of these scanning probes may provide new types of imaging contrast for in a variety of physical systems.  These include nanometer-scale magnetic structures such as domain walls, magnetic vortices, and magnetic skyrmions.  The ability to map mesoscopic current flow in two-dimensional materials and topological insulators or image magnetic field produced by superconducting films and nanostructures could shed light on a number of open questions. 


About the research of the speaker