A dielectric slab waveguide is made from two materials of respective refractive index 1.51 and 1.50. What thickness should the core be in order for the first higher order mode cut-off ; wavelength to be 1 pm? Sketch the field distribution of the fundamental and the first higher order mode for the above case.
The effective index of the fundamental TE mode is 1.505 at an operating wavelength of 1 μm. What is the normalized amplitude of the electric field at the core boundary?