Abstract

I will discuss a new paradigm for physics of dynamics and relativity that is necessary to be consistent with modern cosmology. The fact that the fundamental theories of physics were completed well before any significant knowledge about the real universe and its enormous gravity was available necessitates a re-examination of these theories, especially that of dynamics and relativity. The results of this analysis, along with several experimental facts, reveal that the gravity of the cosmos determines the laws of motion and the propagation of light. In a grand generalization of Machian thought, Newton’s law of motion and the equivalence principle are natural consequences of the gravitational effect in the massive universe. All effects of relativity of motion, like length contraction and time dilation are in fact cosmic gravitational effects. Electrodynamics has physical effects that go beyond special relativity, requiring new experiments and analysis. Indeed, new experiments in our laboratory indicate clearly that the one-way speed of light is not a universal constant relative to moving observers, shattering the most cherished of our beliefs in physics and necessitating replacement of the special theory of relativity with a new ‘Cosmic Relativity’.

Abstract

X-ray multilayers (MLs) – layered synthetic one-dimensional periodic microstructures – are playing an important role in the exploitation of x-rays, particularly soft x-ray/extreme ultra violet (XUV) region of the electromagnetic spectrum. However, understanding basic physics of x-ray MLs and controlling atomic distribution (hence surface/interface) over atomic depth scales in these nano-structured ML systems are crucial for optimum performance of optical elements. In this talk I will present the current state-of-the art research directions in the area of physics (basic and applied) of x-ray ML optics. I will discuss surface/interface studies through representative results of different material combinations. The talk will also cover correlation of structural parameters with tunable properties of x-ray MLs suitable for a variety of applications using synchrotron radiation.The second part of the talk will focus to uncover the underlying mechanism of resonance principle in x-ray scattering technique for basic surface/interface science with high sensitivity and unique additional feature compared to conventional x-ray scattering. Conventional x-ray reflectivity (XRR) probes spatial electron density distribution (within sensitive limit) but not directly atomic composition of the layer. A novel approach will be addressed not only the possible solution to low contrast physics issue of XRR but also an innovative approach to combine structural with chemical analysis using a single resonant scattering technique known for depth resolving sensitivity. We predicted resonant x-ray scattering combines layer sensitivity of reflectivity technique with short-range structural sensitivity such as chemical composition surrounding the resonating atom of spectroscopic technique due to element specificity and contrast variation mechanism of resonance effect. The sensitivity of resonant scattering to the presence of different chemical species around the resonating atoms is analogous to using deuteration as marker in neutron reflectivity. Novel idea will be demonstrated through representative results of different types of basic surface/interface studies near Si L-edge and boron K edge using synchrotron radiation..

Abstract

The potential of surface science towards device fabrication isenormous. However, a trivial surface modification of the substratescan sometime alter the morphology and other properties of thesubstrates as well as the over-layer growth significantly. The kineticand thermodynamic control of the growth processes can form stabilizedlayered and nanostructures. I shall discuss about the 2D layers and 3Dnanostructure formation on the semiconductor and insulator substrateslike, Silicon, GaAs and Sapphire. Not only the various new phasediagrams have been proposed but also some of the existing ones arealso modified. We have used the surface chemical and structuralmodification to render substrate compatibility for epitaxial growth.Some of the examples would include the surface modification of GaAssubstrates for initial GaN formation, kinetically controlled selfassembled nanostructures of GaN and the epitaxial growth ofmultilayered and few-layered graphene on Sapphire substrates. Thegrowth of Graphene on insulator can lead to a breakthrough inutilizing insulator substrates as well for the epitaxial growth ofvarious materials like III-Nitrides.

Abstract

Abstract