Fabrication of single-mode chalcogenide fiber probes for scanning near-field infrared optical microscopy

Abstract

We fabricate scanning near-field optical microscope (IR-SNOM) probe tips made from singlemode chalcogenide fiber and test them using a standard SNOM setup and free-electron laser. SEM micrographs, showing tips with submicrometer physical dimensions, demonstrate the feasibility of the thermal micropipette puller process used to create the tips. Topographical data obtained using a shear-force near-field microscope exhibit spatial resolution in the range of 80 to 100 nm. Optical data in the IR (near 3.5 $\mu$m), using the probe tips in collection mode, indicate an optical spatial resolution of approximately $\lambda/15$.