It is well known that light can be guided within layer(s) having refractive index higher than that of the surroundings by means of the total internal reflection principles. However, using a proper structure, light can also be quasi-confined into layer(s) with refractive indices lower than the surroundings. In this case the light is quasi-guided. In this work, we will show that using proper mathematical tools we can model the latter case of confining light. We used the Galerkin finite element method with Sommerfeld-like boundary conditions to conduct numerical investigations on this class of structures. We investigate numerically the properties of the anti-resonant reflecting optical waveguides (ARROW), leaky step- and graded-index waveguides, planar Bragg and hollow waveguides. Through the modal solutions (i.e. the complex-valued mode indices and modal field profiles), we present an intuitive interpretation of the unique properties of such structures, e.g. the anti-crossing between core and cladding resonance modes in ARROW, the growing-up of field in the high-index substrate/cladding of leaky waveguides, and the relation between Bragg and hollow waveguides.
|Number of pages||19|
|Journal||Journal of the Indonesian Mathematical Society|
|Publication status||Published - 2005|
- IOMS-MIS: MISCELLANEOUS