Cladding propagation

Step-Index Multimode. The step-index multimode fiber has a sharp difference between the index of refraction of the core and that of the cladding (Fig. 16.8a). Light propagation in such a fiber is... 

As aforementioned, the spectral characteristics of LPGs are determined by the coupling between the fundamental guided core mode and the co-propagating cladding modes when the core propagating light encounters a periodic perturbation... 

Stegall, D. B. Erdogan, T., Leaky cladding mode propagation in long period fiber grating devices, IEEE Photon. Technol. Lett. 1999, 11, 343 345... 

Monerie, M., Propagation in doubly clad single mode fibers, IEEE J. Quantum Electron. 1982,... 

Fig. 16.2 Nanoscale optofluidic sensor arrays (NOSA). (a) 3D illustration of a NOSA sensing element. It consists of a ID photonic crystal microcavity, which is evanescently coupled to a Si waveguide, (b) The electric field profile for the fundamental TE mode propagating through an air clad Si waveguide on SiOi. (c) SEM of a NOSA device array. It illustrates how this architecture is capable of two dimensional multiplexing, thus affording a large degree of parallelism, (d) Actual NOSA chip with an aligned PDMS fluidic layer on top. Reprinted from Ref. 37 with permission. 2008 Optical Society of America...

In a ray picture, the wave vector k can be decomposed in a transverse component kx = kT and a propagation vector kz = p. By simultaneously invoking an antiresonance condition for the round-trip phase shift A

cladding material (M> = 2 -k-v + efficient light confinement in the core for a given set of materials is given by ... 

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