Simulation on the near Field Optical Spot of the Waveguide

The paper suggests a new scheme of hybrid recording by high refractive index optical waveguide. A recording bit will be determined by thermal gradient and magnetic field gradient, thermal field gradient be used to determine recording track width, and magnetic field gradient will determine recording bit width. In the scheme thermal gradient will be obtained by laser from an optical waveguide. The optical waveguide is flat structure and composed by three materials. The core is high refractive index material, and the clad is low refractive index material. Theory research and optical coupling transfer efficiency experiment of the wave guide confirm: passive wave guide probe not only can get extreme small near field spot, but also can increase power density of the laser spot.