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We have obtained a simple numerical model that explains the temperature behavior of multi-quantum-dot (QD) nanophotonic devices whose operations are based on optical near-field (ONF) interactions between any two resonant QDs that are in thermal equilibrium. This model involves a set of coupled rate equations that govern the temporal behavior of the QDs' energy level occupancies. Under a certain operating condition, this simple model can substitute for the more complex density matrix (DM) approach in modeling the temperature dependence of the ONF energy transfer rate ([R.sub.ONF]) between any two resonant QDs in thermal equilibrium. The same applies for modeling the system state-filling time ([[tau].sub.S]). Applying our simple model to a two-QD system, we have derived analytical formulas for the interdot and the intradot transfer rates at finite temperatures (T [greater than or equal to] 0). Furthermore, by assuming a unidirectional energy transport operating condition, we have also derived an analytic formula for calculating [[tau].sub.S] for a two-QD system. To the best of our knowledge, this work is the first instance of reporting such analytic equations. Approximated values of [[tau].sub.S] obtained from our simple analytic equation are in reasonable agreements with those calculated by the DM approach. [c] 2010 Optical Society of America OCIS codes: 350.4238, 230.5590.

We propose a new numerical model to analyze heat induced by two-photon absorption and free-carrier absorption, while high intensity optical pulses propagate along silicon-on-insulator (SOI) nanowave-guides (NWGs). Using this model, we demonstrate that such induced heat causes a shift in the amount of wavelength conversion and hence deteriorates the converter output characteristics for pulses in the picosecond regime. The wavelength shift induced by a pulse with maximum input intensity and full width at half-maximum of [I.sub.max] = 1.5 X [10.sup.10] W.[cm.sup.-2] and [T.sub.FWHM] = 30 ps, propagating along a SOI NWG with an effective cross-sectional area of [a.sub.eff] = 0.15 [micro][m.sup.2], is shown to be [DELTA][[lambda].sub.s] = 8 pm. We also demonstrate that such a shift can be compensated by tuning the pump intensity down by approximately 6.33%. OCIS codes: 130.4705, 190.3270, 190.4360, 230.7370, 230.7405.

Chromatic dispersion compensation is an essential feature of high speed dense wavelength-division multiplexing (DWDM) systems. We propose a dispersion compensator structure whose characteristics meet the optical DWDM system requirements. The proposed structure is based on Fibonacci quasi-periodic multilayer structures composed of layers with large index differences. Studying the dispersive properties of Fibonacci structures with generation numbers j = 3 and 4, and calculating group delay (GD) and group velocity dispersion (GVD) of their reflection bands, we have demonstrated that to have a smooth GD and almost a constant GVD in each band of a DWDM system, one needs not only to suitably chirp the structure refractive index profile, but also must properly apodize it. We also demonstrate the possibility of achieving high slope GDs and large GVDs by means of high order Fibonacci structures with thicker layers. Finally, by varying the layer dimensions and refractive indices as well as Fibonacci's order, one can design DWDM dispersion compensators suitable for distances as long as 220 km. OCIS codes: 050.1590, 060.4510, 230.2035, 220.1230, 230.4170, 130.2035.