Development of tapered silver-halide fiber tips for a scanning near-field microscope operating in the middle infrared

We have constructed a scanning near-field infrared microscope (SNIM) which was based on a AgClBr fiber probe whose end was etched to form an aperture of a subwavelength diameter. A detailed study of the mechanical properties of a vibrating AgClBr probe was required for proper operation of the SNIM system. We have demonstrated that the system can be used for imaging and for topographic mapping of samples with a subwavelength resolution in the middle infrared. Such a SNIM will be a powerful tool for the study of microelectronic components or subcellular structures in biological cells.