ECE 4332 ELECTR OOPTIC DEVICES AND SYSTEMS Assignment

ECE 4332 ELECTR OOPTIC DEVICES AND SYSTEMS - Assignment ExampleAccompanying the evolution from copper wire or wireless connection to light gesture networks is the proliferation of new optical devices. Discoveries in optical transmitters, amplifiers, frequency converters, filters and multiplexers enable ways to generate, condition, and detect light.The study of wave interactions with periodic structures has yielded convenient methods of depth psychology and the results have been extended to gratings in wavelengths such as those in distributed feedback lasers, acousto-optic modulators and filters, and other diffracted waveguide devices. The fiber Bragg gratings is readily analyzed by coupled mode and point matrixes analysis. the two modes of the waveguide Bragg grating are the counter propagating waves in the fiber which are coupled through the grating reflection. In the absence of the grating, the spatial colony of the polarization currents for the forward wave are proportional to. Perturbations by a grating having spatial period create new sidebands that result in wave coupling i.e. exp( jz)cos(2z/) = expj(-2/)z+expj(+2/)z and mode coupling to the backward coupling wave. Exp-jz described by the first term on the right-hand side, occurs when -(-2/). hence the forward propagating wave is reflected (coupled) into the backward propagating wave.Coupled mode comparisons are readily derived upon substitution by the grating refractive index function into the wave equation +2E()=0 where =koz is the normalized axial dimension and n()/no=1+()+2h()cos2+2(). Here, no is the effective index of the propagating waves, and k0=onok is the nominal Bragg wave number, for constant , the Bragg wavelength is bragg=2n0/k0. Change in the local average refractive index is defined by , the peak-to-peak index variation is 4h and corresponds to grating