Fabrication of a phase photon sieve on an optical fiber tip by focused ion beam nanomachining for improved fiber to silicon photonics waveguide light coupling.

We report the fabrication of a phase photon sieve (PS) on the tip of a standard single mode fiber by focused ion beam (FIB) milling. The fiber tip was dip-coated with a conductive polymer ( PEDOT: PSS) as an alternative, more advantageous method to the metallization prior to FIB milling. The near field scans of the intensity profile along the optical axis under fiber illumination of a laser at λ = 1.55 μm are presented. We have analyzed the focusing properties and demonstrated the validity of our structure for light coupling into silicon photonics waveguides with improved efficiency and alignment tolerance.