In this thesis, we propose a potentially inexpensive light source for the mulit-channel wavelength division multiplexing (WDM) system applications. The spectrum-sliced incoherent light source (SILS) is alternative conventional laser source for the WDM system owing to its simplicity and flexibility. However, the spectrum-sliced source suffers from the intensity noise and spontaneous-spontaneous beat noise. Thus, it is necessary to increase the optical bandwidth or decrease the electrical bandwidth (by varying the bit rate ) to improve the signal to noise ratio (SNR). We used the intra-channel four wave mixing (IC-FWM device) before the receiver to suppresses the intensity noise of the light source, thus greatly expands the optical bandwidth of the received signal. We not only demonstrated the capability of an 8 ¡Ñ 2.5 Gb/s, DWDM with 200 GHz channel spacing transmission system by utilizing only one spectrum-sliced source, but also investigate the cross-talk issue of SILS in the fiber Bragg grating-based optical add/drop multiplexer (FBG-based OADM) and the Mach-Zehnder fiber Bragg grating-based optical add/drop multiplexer (MZ FBG-based OADM) systems.

My research on the new concepts for spectrometer has been focused on the development of true multi-dimensional spectrometers, which use a multi-dimensional [two-dimensional (2D) or 3D] mapping of the spectral information into space. I showed that by combining a simple dispersive element (a volume hologram) formed in very inexpensive polymers with a basic Fabry-Perot interferometer, we can form a spectrometer with ultra-high resolution over a large spectral bandwidth, which surpasses all conventional spectrometers. I strongly believe that the extension of this mapping into three dimensions by using synthetic nanophotonic structures with engineered dispersion can further improve the performance and reduce the overall spectrometer size into the micron regime. The need for efficient modeling and simulation tools comes from the sophisticated nature of the new 3D nanophotonic structures, which makes their simple analysis using well-known simple formulas for the propagation of the electromagnetic fields in bulk materials impossible. In my Ph.D. research, I developed new approximate modeling tools for both the modeling of incoherent sources in nanophotonics, and for the propagation of such optical beams inside the 3D nanophotonic structures of interest with several orders of magnitude improvement in the simulation speed for practical size devices without sacrificing accuracy. To enable new dispersive properties using a single nanophotonic structure, I have focused in my Ph.D. research into polymer-based 3D photonic crystals, which can be engineered using their geometrical features to demonstrate unique dispersive properties in three dimensions that cannot be matched by any bulk material even with orders of magnitude larger sizes. I have demonstrated the possibilities of using a very compact structure for wavelength demultiplexing and also for spectroscopy without adding any other device.