High-quality metamaterial dispersive grating on the facet of an optical fiber

Bragg gratings fabricated along the mode propagation direction in optical fibers are a powerful technology for controlling dispersion. Here, we show that a dielectric metamaterial grating with sub-wavelength period fabricated in the thin layer of silicon on the fiber facet exhibits transmission resonance with the quality factor exceeding 300. We demonstrate how focused ion beam patterning, commonly expected to degrade the optical performance of materials, can be exploited to create low-loss photonic nanostructures on the fiber facet. Only a few tens of nanometers in thickness, such facet gratings can be used in compact interconnects, dispersion compensation, and sensing applications.