Low-temperature scanning force microscopy using a tuning fork transducer

We developed a low-temperature scanning force microscope using a quartz tuning fork operating at 4.2 K. A silicon tip from a commercial cantilever was attached to one prong of the tuning fork. With a metallic coating, a potential could be applied to the tip to sense the charge distribution in a sample while with a magnetically coated tip, magnetic force imaging could be performed. For the coarse approach mechanism, we developed a reliable low-temperature walker with low material cost and simple machining. We obtained Coulomb force images of boron nanowires at room temperature and of magnetic nano-structures at low temperature. With the tuning-fork-based magnetic force microscopy (MFM) probe, low-temperature MFM was performed at 77 K and 4.2 K in a high magnetic field (up to 3 T) by using a superconducting.