Nanoparticle manipulation with a carbon fiber tip in an electron microscope for µ-SQUID magnetometry

We report a carbon-fiber-tip based nanomanipulation system integrated into a scanning electron microscope for individual nanoparticle (NP) manipulation on a surface. Electrochemically etched amorphous carbon fiber tips with excellent mechanical rigidity and sub-100 nm apex radii, effectively reduce the van der Waals adhesion and enable reliable positioning of about 100 nm size NPs with about 100 nm precision. This system combines a piezoelectric bimorph for vertical tip motion, a four-quadrant piezo-tube for two-dimensional fine tip control and a two-dimensional piezoelectric walker for coarse lateral translation. Using this setup, we successfully position single Fe3O4 magnetic NPs on micron sized superconducting quantum interference devices for optimal magnetic coupling between them and probe a NP's magnetism.