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According to the Bloch theorem and the symmetry of superlattice configuration, a new 3D finite element method is employed to calculate the miniband structure and density of state for well-aligned Ge/Si QDs array. This method can overcome the approximation of multi-dimensional Kronig-Penny model and constrain on QDs superlattice structure. The interaction of electronic structure among Ge/Si QDs with...
In this work, an efficient method is applied to calculate the miniband structure and density of states for well-ordered Ge/Si quantum dot (QD) array fabricated by combining the self-assemble bio-template and damage-free neutral beam etching. Within the envelop-function framework, this computational model surmounts theoretical approximations of the multi-dimensional Kronig-Penney method and the numerical...
We demonstrate a two-dimensional photonic crystal made of PECVD silicon carbide (SiC) at near-infrared wavelengths. Although the refractive index of SiC is lower than that of a conventional semiconductor such as GaAs or Si, we show that photonic crystals based sensors can be obtained in PECVD SiC. We fabricated photonic crystals experimentally having bandgaps of 200 nm, and estimated their sensitivity...
Two-dimensional photonic crystals (PCs) are fabricated by using the wet chemical etching of high-resistivity silicon. The formation of the photonic band gap at a frequency of about 100 GHz is demonstrated by the measured and the 3D FDTD simulated transmittance of the transverse magnetic (TM) mode.
Transparent silicon solar cells can lead to increased energy conversion efficiency by enabling the collection and conversion of photons near and below the silicon band gap. This can be accomplished through the use of a low band gap solar cell in multiple junction systems. This analysis shows that the potential energy conversion efficiency gain for a one sun system is 7%. The design and fabrication...
E-beam evaporated LaF3 passivation of porous silicon (PS) has been investigated in this report. Heat treatment of the LaF{in3-passivated PS structure improves the PL characteristics. Passivation with thinner layer of LaF{in3 leaded to a good enhancement of photoluminescence intensity while thicker layer showed stabilization of photoluminescence.
A novel macro-via crystal (MVPC) structure is proposed for suppression of PPNs in high-speed or mixed signal circuit package. This structure is designed by periodically embedding macro-via cylinders, which consist of six vias and two circular pads, between the power and ground planes. Compared with previously proposed EBG structures, several advantages have been demonstrated. First, etching slots...
One-dimensional (1-D) photonic crystal with photonic band-gap based on porous silicon is fabricated with alternative etching currents during anodization. The microstructure was characterized by scanning electron microscopy and the optical reflectance spectra by Fourier transform infrared spectroscopy. A band-gap centered at 6 microns with a bandwidth of 3 microns has been successfully obtained. The...
Summary form only given. A simple cubic (SC) structure exhibiting a photonic band gap (PBG) was proposed by Sozuer and Haus (1993). Recently, Wada et al. (1997) reported a comparison between the FTIR transmission spectra of a pseudo-simple cubic lattice with theoretical transfer matrix results. The sample is composed of air rods with square and circular shaped rods made of silicon with the respective...
Summary form only given. Planar photonic crystal waveguides and devices may offer the possibility to build photonic circuits with greater density and new functionality compared to existing waveguide devices that are based on the control of light by refraction. The primary vehicles for this research are the study of microcavity lasers as a path to understanding new functionality, and the propagation...
Summary form only given. The use of planar microcavity structures to control spontaneous emission from optical devices is now a well-established technique. The simplest geometry is that of a pair of planar mirrors separated by a distance of order the wavelength of light, with the emissive species situated between the two mirrors. It has been clearly demonstrated that the boundary conditions imposed...
Summary form only given. Introducing a line defect into a photonic crystal can create localized states within the photonic band gap of the crystal. Such a defect behaves as a waveguide, where the confinement of the light occurs via the photonic band gap (PBG) rather than total internal reflection. Aside from some recent optical experiments, most qualitative studies of photonic crystal waveguides have...
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