Preparation of high energy throughput SNOM probes

In this technical note we present technological steps of fabrication of high energy throughput SNOM probes. The core-metal coating interface of probes is corrugated what enhances photon-to-plasmon coupling. A strong evanescent field allows for reduction of aperture diameter, which together with skin depth of metal used for coating decide upon resolution. Probes are made of Ge-doped silica glass fibre, which is hydrogenated to increase its photosensitivity. A Bragg grating is recorded in the cores with UV light diffracted into +1
^st
/-1
^st
diffraction orders on a sinusoidal phase mask. Modulation of the refractive index is connected with different etch rates. Etching with the Turner method is made in aqueous solution of HF acid. A corrugated tapered fibre is then coated with aluminium in a special rotating holder. We present results of this novel multi step technology.