Question

Consider a symmetric slab waveguide (or a circular step-index fiber waveguide). If all parameters are held constant except the index of refraction difference between the core and the cladding increases, will the fraction of the energy (of the fundamental propagating mode) in the cladding regions increase, decrease, or remain the same? Explain your answer in detail.

Answer 1

Dear student,

In this type of optical waveguide which we get after winding, the pitch angle controls the model characteristics of the optical waveguide.

When the core and cladding regions are interfaced, a total internal reflection may be created. during this whole phenomenone complete energy is reflected to return direction towards core with no energy transmitted to the cladding layer. if we talk about the refractive index of the cladding layer then it is always lowered then that of the core. with the continuity of this condition, no energy transfer takes place into the cladding layer.

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