Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 61 for “"light propagation"”.
-
Light Propagation in Ultracold Atomic Gases
The propagation of light through an ultracold atomic gas is the main topic of the present work. The thesis consists of two parts. In Part I (Chapters 1,2,3), we give a complete description of the 1D photonic bands of a MI of two-level atoms paying attention to both band diagrams and reflectivity …
-
Applications of light propagation in novel photonic devices
In this thesis, the propagation of light in novel photonic devices has been studied theoretically, numerically and experimentally. In particular, self-similar solutions to the nonlinear Schrödinger equation have been investigated as a means of avoiding distortions associated with high power pulse …
-
Holographic Control of Light Propagation in Optical Waveguides
… can now be used to control every aspect of light propagation along an optical waveguide. The application of holographic techniques offers the possibility of faster communication technologies, ultra-thin endoscopes and holographically enhanced sensors. An experimental system is established …
-
Light propagation in a weakly perturbed expanding universe
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1995.
-
Spatially resolved light propagation in tissue-like media
The work presented in this thesis is part of a larger project designed to monitor and diagnose Alzheimer's disease non-invasively in vivo using spatially resolved nearinfrared (NIR) spectroscopy. Alzheimer's disease is one of the most common forms of senile dementia occurring in the elderly …
-
The effects of light propagation in spherically symmetric metrics.
Massachusetts Institute of Technology. Dept. of Physics. Thesis. 1969. Ph.D.
-
Modeling of light propagation in skin, and an application to noninvasive diagnostics
… an effect which is based upon changes of the light scattering coefficient in the upper dermal regions of skin induced by glucose dissolved in the interstitial fluid. We will focus on the identification of this coefficient in vivo. As we want to probe our tissue with decoherent light of a …
-
Modelling and simulation of light propagation in non-aged and aged step-index polymer optical fibres
Kunststofflichtwellenleiter (POFs) stellen ein verhältnismäßig neues Medium zur optische Datenkommunikation über kurzen Strecken dar. Während ihrer Einsatzdauer unterliegen POFs unterschiedlichen Arten von Umweltbeanspruchungen, hauptsächlich durch hohe Temperatur, hohe Feuchtigkeit und …
-
Electrohydrodynamic focusing and light propagation in 2-dimensional microfluidic devices for preconcentration of low abundance bioanalytes
… Numerical models and experimental validation of light propagation and light intensity distribution in 2D microfluidic systems was examined. The developed numerical mode of light propagation was used to calculate the actual light path through the system and the light intensity distribution. The …
-
Integrated full vectorial FEM, FDTD and diffraction integrals in characterising visible light propagation through lossy biological media
In this thesis, the propagation characteristics of the biological optical waveguides, considering the materials as lossy in the optical frequencies, have been analysed. It has been found that the losses present in the biological materials in optical frequencies are not negligible, and the loss …
-
Three dimensional simulation of functional neuro-vascular imaging
… In both FLIM and LSCI, for example, only the light which samples the intravascular space will contribute to the signal. While analytical methods have proven to be successful at predicting the imaging depth of homogeneous materials, they are not able to predict imaging depth when measuring a …
-
Photonic Crystals with Alternate Arrays of Rods and Holes in a Low Dielectric-Index Material
<p>This thesis theoretically deals with the propagation of electromagnetic waves (light beams) in periodically modulated dielectric material structures based on Maxwell’s equations. We are interested in novel light propagation characteristics in these man-made dielectric material structures for …
-
Light-matter interaction in silicon nanophotonic structures
In this thesis light matter interactions in the weak coupling regime are investigated in Si-based photonic devices. At first, spectroscopic investigation of energy transfer among Er ions and Si-nanoparticles for optical amplification has been reported. Successively, light propagation in dielectric …
-
A novel ultra-low refractive index nanoporous dielectric based aqueous core waveguide system
… an on-chip waveguide system capable of guiding light through aqueous solutions. The waveguide relies on total internal reflection for light propagation wherein the core of the waveguide consists of the aqueous solution. The relatively low refractive index of aqueous solutions places a serious …
-
LARGE AREA 3D PHOTONIC CRYSTALS WITH EMBEDDED WAVEGUIDES
… that manipulate and control the properties of light propagation. Photonic crystals are analogous to semiconductor crystals with periodic potentials that are responsible for the bandgaps for electrons and holes. For electrons and holes, the periodic potential effectively determines how the …
-
A study of periodic gratings in planar dielectric waveguides
… waveguides is presented. The analysis of light propagation in a planar dielectric waveguide with sinusoidal boundary perturbations is carried out using coupled-mode theory. Power reflection and transmission coefficients are calculated for single gratings as well as two gratings of the same …
-
On the use of prior knowledge in deep learning algorithms
… retrieval. We use our prior knowledge of the light propagation, and embed an approximation of the physical model into our training scheme. We test this on imaging in extremely dark conditions with as low as 1 photon per pixel on average. Secondly, we investigate the case of image-enhancement. …
-
Constraining the Magneto-Ionic Environment of Galactic Supernova Remnants
… we know the distribution of electrons along the light propagation path. Historically, this technique is most often applied to unresolved compact sources, but analysis of these sources only provide us information about the line-of-sight magnetic field. My research focuses on applying a similar …
-
Brillouin scattering induced transparency and generation of slow and fast light
… to estimate BSIT's effect on the velocity of light pulse. As BSIT modifies the dispersion of light, it is understood as either slowing or advancing light propagation depending on the sign of the slope of the probe phase response. Lastly, the non-reciprocity of Brillouin scattering is …
Page 1 of 4