Ultra-thin Bloch-surface-wave-based reflector at telecommunication wavelength

We experimentally demonstrate the optical properties of gratings engraved in a single-mode waveguide fabricated on top of a dielectric multilayer platform. The structure can be approached as a reflector for Bloch-surface-wavebased two-dimensional optical systems. The gratings have been fabricated on a thin (∼λ∕25) titanium dioxide layer with a thickness of a few tens of nanometers deposited on the top of a multilayer platform. The optical properties of the gratings have been characterized in the near field with the aid of multi-heterodyne scanning nearfield optical microscopy. We investigate the surface wave’s interference pattern, produced by incident and reflected light in front of the gratings. The presented gratings behave as an efficient Bloch-surface–wave-based reflector at telecommunication wavelength.