ABSTRACT
Germanium-on-silicon thermo-optic phase shifters are demonstrated in the 5 µm wavelength range. Basic phase shifters require 700 mW of power for a 2π phase shift. The required power is brought down to 80 mW by complete undercut using focused ion beam. Finally an efficient thermo-optic phase shifter is demonstrated on the germanium on SOI platform. A tuning power (for a 2π phase shift) of 105 mW is achieved for a Ge-on-SOI structure which is lowered to 16 mW for a free standing phase shifter.
Subject(s)
Germanium/chemistry , Optical Phenomena , Silicon/chemistry , Spectrophotometry, Infrared/instrumentation , Temperature , Absorption, Radiation , Computer Simulation , Interferometry , Microscopy, Electron, ScanningABSTRACT
We demonstrate a new kind of single-mode micro-optical waveguide based on a liquid core on top of solid substrate and air cladding. The liquid is held in place by surface tension and patterned surface energy on the substrate. Due to the smooth nature of the liquid/air interface down to the molecular level, low scattering losses are expected. Losses were measured to be -6.0 and -7.8 dB/cm for, respectively, 12 and 9 µm wide waveguides.
