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The semiconductor industry has seen a remarkable miniaturization trend, driven by innovations in nanofabrication and nanoscale characterization [1]. Semiconductor technology can currently manufacture devices with feature size less than 100 nm. A modern microprocessor can have more than 500 million transistors. Electronic integrated circuits are inherently single-channel connected device arrays within a two-dimensional printed circuit board [2]. By further shrinking transistor size, one approaches the technical, physical, and economical limits, which will be reached within a few years [3]. At the same time, the insulating layer is also getting thinner leading to an enhancement in the current leakage and resulting in short circuit [4]. Manufacture cost increases drastically with further size reduction. As this trend is likely to yield faster and compact electronic and photonic devices, the size of microelectronic circuit components will soon need to reach the scale of atoms or molecules [1]. Those limitations and application requirements inspired extensive research aimed at developing new materials, device concepts, and fabrication approaches that may enable the integrated devices to overcome the limitations of the conventional microelectronic technology. This will require a conceptual design of new device structures beyond CMOS technology which may require alternative materials to overcome these limits. Hybrid organic–inorganic system is one of the alternative solutions. [ABSTRACT FROM AUTHOR]

We present the characteristics and applications of photonic crystal ring resonators (PCRR). Photonic crystal confinement can achieve very high cavity quality factor ring resonators. Diffraction-limited ultra-compact PCRRs are feasible due to the absence of size-dependent losses. The flexible modal properties can offer flexible design and integration schemes for either forward or backward propagating add-drop filters based on single- or dual-ring PCRRs. Hybrid-confined PCRRs also show great potential and useful characteristics. Furthermore, we report a few device and circuit configurations based on PCRRs for high-speed modulators, filters, delay lines, etc. Such PCRR structures can potentially provide a good alternative to the traditional microring resonators, as one of the key contributors to the emerging low-power nanophotonics technology. [ABSTRACT FROM AUTHOR]

In this chapter, we present a general theory of effective media to establish the relationship between the local field responses on metamaterial structure and the macroscopical behaviors for artificial metamaterials composed of periodic resonant structures. By treating the unit cell of the periodic structure as a particle, we average the local field to define the local average permittivity and permeability for different unit structures and derive a general form of discrete Maxwell΄s equations in macroscale. We obtain different wave modes in metamaterials including propagation mode, pure plasma mode, and resonant crystal bandgap mode. The distortion in the electromagnetic parameters has been well explained by the derived spatial dispersion model. Thus, the unfamiliar behaviors of metamaterials from the numerical S-parameter retrieval approach is further verified and described. The excellent agreements between the theoretical predictions and the numerical retrieval results indicate that the new defined model and method of analysis fit better to the physical structures and is thereafter a more advanced form of fitting formula for the effective electromagnetic parameters of metamaterials. [ABSTRACT FROM AUTHOR]

This paper presents an overview of our recent activity on fabrication and investigation of three-dimensional opal-semiconductor and opal-metal photonic crystals. The main goal of our work is to create materials where functional properties of opal pore fillers could be combined with unique features of photonic crystals based on synthetic opals. The novel properties of such materials open new possibilities to mould and control emission and propagation of light in visible and near-infrared photonic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Singular states of photonic crystal local optical field are described based on group theoretic treatments of the fundamental system symmetries expressed through local representations of the singular character of the Bloch modes. The local field response is illustrated, in a purely two-dimensional system for clarity, by an analysis of the local polarization state. The fundamentals of group theory are introduced through the group representation, whose partner functions may be used to express the photonic crystal eigenmodes. We have extended the eigenmode k-group treatment to the derivation of the irreducible matrix representations of the transformation operators of the eigenmode space k-group, which may be applied with respect to any symmetry axis. This permits a comprehensive discussion of the local polarization state, and its symmetry transformation properties, through the set of crystallographic orbits. Transformation relations permit the nature and location of polarization singularities to be identified by the sites' Wyckoff positions. Confirmation with analytic mode determination is presented. [ABSTRACT FROM AUTHOR]

We show the deterministic coupling of the MOCVD InGaAS/GaAs dots to photonic crystal nanocavities. The unique properties of the fabrication technique offer a complete control on the emission properties due to the small inhomogeneous broadening of QDs inside the photonic crystal. The PL-Spectroscopy of the system shows that the coupling of the QDs to photonic crystal nanocavity is satisfied with a small mismatch of 50 nm in wavelength. We discuss the weak coupling regime theoretically and show that how spontaneous emission can be enhanced by putting the dots inside photonic crystal nanocavity. We have checked the enhancement of spontaneous emission as a direct result of Purcell effect. The system can be used as an efficient source of solid state single photon emission for quantum computing, quantum cryptography as well as for fundamental quantum optics experiments such as cavity QED experiments. [ABSTRACT FROM AUTHOR]

Photonic sensors are under extensive development world-wide combining multidisciplinary research. Small, inexpensive, sensitive, selective, fast, robust, and remotely controllable sensors that are immune to electromagnetic interference are the ultimate goal. The potential to achieve these capabilities has been demonstrated through different photonic sensor designs and developments in photonic structures. Progress in materials, light sources, photodetectors, and innovative solutions have driven the technology further. This paper focuses on new trends for photonic sensors with applications in health and environmental monitoring. [ABSTRACT FROM AUTHOR]

Blue phases are known to appear in chiral liquid crystals in a small temperature range between the chiral nematic phase and the isotropic one. They are optically active, non-birefringent, and they show Bragg diffraction of light in the visible wavelength, measuring several hundred nanometers. Their exotic structures and properties result from the competition between chiral forces and packing topology. Recently, the blue phases have attracted the attention in the field of optoelectronics and photonics. The following article summarizes the basic properties, especially the frustration in the double twist molecular alignment which is the origin of stabilization of the blue phase, and history of the blue phase studies, and describes significant advances that have been recently reported. [ABSTRACT FROM AUTHOR]