A magnetic write head is disclosed that includes a slider that includes a laser diode having a light-emitting edge or surface of a laser diode and an optical waveguide. The disclosed magnetic write head also includes a dielectric layer disposed in a gap between the laser diode and an input to the optical waveguide. The dielectric layer fills the gap completely and provides a low-loss optical pathway for the laser diode to the input of the optical waveguide. Also disclosed is a method that includes spinning on a dielectric in a gap between the light-emitting surface and the optical waveguide coupler, wherein after the spinning on, the laser diode is optically coupled to the optical waveguide coupler through the dielectric.