Patent attributes
Methods and apparatuses for mode conversion. An apparatus that includes a substrate, a first waveguide, a second waveguide, a micro-electro-mechanical systems (MEMS) perturber, and a controller is provided. The first waveguide is formed on the substrate includes: (i) an input section, (ii) a bend section, and (iii) an output section. The second waveguide is also formed on the substrate and is disposed adjacent to a portion of the input section of the first waveguide. A portion of the second waveguide is separated from the input section of the first waveguide by a coupling gap. The perturber is disposed above the first waveguide and configured to move between a first position that is distal from a surface of the input section of the first waveguide and a second position that is closer to the surface of the input section of the first waveguide than the second position. The controller is configured to control a movement of the perturber between the first position and the second position. When the perturber is in the first position, a mode effective refractive index of the first waveguide is lower than the mode effective refractive index of the first waveguide when the perturber is in the second position.