Photonic Band Gap Materials:  A little history behind Photonic Band Gap materials (PBG)? In 1987, an American physicist and engineer named Eli Yablonovitch and Canadian physics professor from the University of Toronto Canada, Sajeev John constructed artificial structures that then became the concept of PBG material. In order to evaluate this concept they created a 3D prototype diamond lattice in Plexiglas, which is a type of acrylic glass material. With this creation they were able
ligand charge transfer) change. The energized electrons are inserted into the conduction band of the Titanium Oxide electrode, consequential in the oxidation of the Photo-Sensitizer S + hν →S∗ [1] S∗ → S+ +e− (Titanium Oxide) [2] 3. Inserted electrons in the conduction band of Titanium Oxide are moved b/w Titanium Oxide Nano-particles with dispersal towards
CHAPTER 1 1.0 INTRODUCTION Energy is essential to meeting basic human needs: food, heat, light and transportation. Poor access to energy impacts on quality of life, education chances, economic production and healthcare provision. According to the International Energy Agency, 1.5 billion people around the world lack access to electricity-85% of them in rural areas. 2.7 billion People rely on traditional use of biomass and that number is expected to rise to 2.8 billion by 2030. Most of our energy comes
Synchrotron radiation is electromagnetism field radiated by accelerating charge particles. The applications of Synchrotron are in many fields e.g. Nano-science, Molecular science, biology and Magnetism.....etc. There are many techniques which based on synchrotron for instance: x-ray diffraction, infrared microscopy techniques and others yet to be developed [1].In this essay, we will focus on the x-ray technique based on synchrotron radiation used on silicon solar cell. However, the x-ray technique
Nathaniel Mackey's Bedouin Hornbook A Bedouin is a nomad and a nomad a wanderer. Nathaniel Mackey seems to wander far and away in his Bedouin Hornbook, a series of fictional letters addressed to an “Angel of Dust” and signed by the ambiguous “N.” N. interprets passages of improvisation, analyzing others’ musical expression in surprising detail to the point that his unquestioning sincerity and self-assurance are almost laughable. That N. can glean meaning from music in such a direct and certain
Introduction To begin this report, we will describe what exactly are “Compound Semiconductor Solar Cells”, by first separating the two main parts of “Compound Semiconductor” and “Solar Cell”. Firstly, a compound semiconductor is a semiconductor made up of two or more elements, such as Gallium Arsenide (GaAs), which is composed of Gallium (Ga) from Group III and Arsenic (As) from Group V. Compound Semiconductors have several important advantages over the conventional semiconductors which are made
kinetic energy levels, which increase with the orbital radius. When atoms bond together to form a solid, the electron energy levels merge into bands. In electrical conductors, these bands are continuous but in insulators and semiconductors there is an "energy gap", in which no electron orbits can exist, between the inner valence band and outer conduction band [Book 1]. Valence electrons help to bind together the atoms in a solid by orbiting 2 adjacent nucleii, while conduction electrons, being less
that is why the electronic properties of graphene depend strongly on the number of graphene layers. Hence, only single-layer and bilayer graphene are zero band gap semiconductors which means there is no energy gap between the valence band and the conduction band. On the other hand, in the case of few-layer graphene, the conduction and valence bands start to overlap. Because of this kind of properties, graphene exhibits unique electrical properties such as having high carrier mobility, a stable 2D crystal
definitely seen a store owned by Gap Inc. such as stores like Old Navy, Gap, Banana Republic, Etc. These stores represent an ionic and proud American store since 1969 which has multiplied since they opened their first store in San Francisco. This marked the first of many stores that would open and take over America. Gap became an icon as it started to multiply as larger variety stores came about. Such stores as Old Navy taking over the lower budget gap clothing to Gap as a middle budget and on to Banana
novelistically. When no facts are available, the author may extrapolate missing parts of the story from two sources -- either through the interpretation of the existing scholarly data or through the author's imagination. These two approaches to 'filling in the gaps' of a historical novel can either appease the historian and displease the literary critic or please the literary critic and upset the historian. Very few novelists can produce a historically accurate novel that is also pleasing to a literary critic;