Photonic crystal

About: Photonic crystal is a research topic. Over the lifetime, 43424 publications have been published within this topic receiving 887083 citations.

The Race for the Photonic Chip: Colloidal Crystal Assembly in Silicon Wafers

Abstract: This paper surveys recent developments in engineering physics approaches and self-assembly chemistry methodologies for creating 3D photonic crystals and how this has led to in-wafer patterned colloidal crystals. These materials are comprised of single crystal micrometer scale features of silica colloidal crystals that have controlled thickness, area, and orientation and are embedded within a single crystal silicon wafer. Two processes for growing opal-patterned chips are described. One is based upon microfluidic and the other spin coating driven self-assembly of colloidal silica micro-spheres within a lithographic patterned silicon wafer.

Self‐Assembly Approaches to Three‐Dimensional Photonic Crystals

Abstract: A brief review of the historical development of photonic bandgap (PBG) materials is provided and the fabrication methods employed are discussed with emphasis on self-assembly processes. The factors influencing the generation of a complete bandgap, from both an experimental and a calculational standpoint are then presented and discussed. The Figure shows a diamond-like 3D periodic structure.

Photonic crystal laser sources for chemical detection

Abstract: A system, method and apparatus provide the ability to detect a chemical in an analyte. To detect the chemical, the invention utilizes a laser having an open cavity. A photonic crystal lattice structure having a defect defines a suitable geometry for such a cavity (1000). The analyte is introduced directly into a high optical field of the cavity (1002). Thereafter, the cavity is pumped (1004) and an emission from the laser is used to detect the presence of the chemical (1006) in the analyte.

Photonic Band Gap Structures

Abstract: Nanotechnology is a scientific frontier with enormous possibilities. Reducing the size of objects to nanometer scale to physically manipulate the electronic or structural properties offers a fabrication challenge with a large payoff. Nanophotonics is a subfleld of nanotechnology and a part of nanophotonics includes photonic band gap structures, which manipulate the properties of light to enable new applications by periodically modulating the relative permittivity. In photonic band gap (PBG) structures, the electromagnetic properties of materials, such as the electromagnetic density of states, phase, group velocities, signal velocities, field confinement, and field polarization are precisely controlled. The size scale of interest in PBG structures is typically of the order of a wavelength, which is not quite as demanding as required to observe quantum confinement effects in electronic materials. Nevertheless, photonic devices designed with nanophotonic technology enable new technology for devices and applications in sensing, characterization, and fabrication. Even though PBG photonic devices are complex and the fabrication is often expensive, rapid progress on PBG structures has been possible because of the development of powerful numerical computation tools that provide a detailed analysis of the electromagnetic properties of the system prior to fabrication. To design photonic devices we use a variety of computational techniques that help in evaluating performance. Several books have already been written about the optical properties of PBGs. A classic book on ID periodic structures was written by Brillouin. Yariv and Yeh's book is an excellent resource on many aspects of periodic optical media. Recent books devoted to the subject include the books by Joannopoulos et al., the very thorough book by Sakoda, and a recent book on nonlinear optics of PBGs by Slusher and Eggleton that features results of several researchers who have contributed to the subject. In addition, many good articles on PBG structures can be found in special issues or in summer school proceedings. Numerical approaches are available to completely describe the properties of electromagnetic wave propagation in PBG structures. Three methods are of general use; they are the plane wave, the transfer matrix, and the finite-difference time-domain (FDTD) methods. The results of the plane wave method with the latter two are to some degree complementary, as is demonstrated and discussed later in this chapter. Analytical methods are also available and have been especially useful for 1D systems. For instance, the development of coupled-mode equations for propagation by using multiple scales or slowly varying amplitude methods has given researchers powerful tools for studying nonlinear effects and designing new electro-optic (EO) devices, such as tunable optical sources from the ultraviolet to the terahertz regime, EO modulators, and a new generation of sensitive bio/ˆ•chem sensors.

All-optical transistor action with bistable switching in a photonic crystal cross-waveguide geometry

Abstract: We demonstrate all-optical switching action in a nonlinear photonic crystal cross-waveguide geometry with instantaneous Kerr nonlinearity, in which the transmission of a signal can be reversibly switched on and off by a control input. Our geometry accomplishes both spatial and spectral separation between the signal and the control in the nonlinear regime. The device occupies a small footprint of a few micrometers squared and requires only a few milliwatts of power at a 10-Gbit/s switching rate by use of Kerr nonlinearity in AlGaAs below half the electronic bandgap. We also show that the switching dynamics, as revealed by both coupled-mode theory and finite-difference time domain simulations, exhibits collective behavior that can be exploited to generate high-contrast logic levels and all-optical memory.