| In this dissertation I implement photonic and terahertz integrated circuits through the exploration of photonic crystals. The progressive approach to the limitation of integrated electric circuits, due to the explosive growth in this field, bring about interest in photonic integrated circuits. Scientists have expected such photonic integrated circuits to create advanced systems with low-power dissipation, high bandwidth, high speed and ultrasmall integrated circuits. Among the common layouts of photonic circuits, 2D-photonic crystals, because of their ability to manipulate light and their advantages in integration, have been especially attractive to the science community. However, most of the studies on 2D-photonic crystals are focused on properties in which light enters the slabs in-plane, and little work has been dedicated to the properties resulting from light vertically entering the PhC. In the latter case, photonic crystals exhibit significantly different properties than cases of in-plane entry. These properties create a brand new dimension for photonic crystal applications. To explore this potential, I present the first experimental results of a series of simple yet efficient spectral filters based on light that vertically enters the PhCs. In addition, in order to realize the ultimate goal of integrating different devices into a circuit, I propose a new concept of hybrid lattices and their associate properties to design devices. The successful demonstration of the hybrid devices including waveguides, directional couplers, and wavelength division multiplexers displays the potential of this hybrid concept to create a new paradigm for designing devices.; Furthermore, for integrated circuits, the efficient coupling between free-space electromagnetic waves and circuits and the connections among different devices are critical for the widespread application of these systems. To address these issues, I demonstrate the use of a prism-coupling and a photonic crystal-coupling lens to couple terahertz (THz) waves from free space and between different devices. Both methods are confirmed to be very efficient. Finally, THz PhC line-defect and self-collimation waveguides, along with wavelength division multiplexers (WDMs) are also presented to fill the lack of research in this field. |
