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Other Materials Science and Engineering

Theses and Dissertations

Theses/Dissertations

2010

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Full-Text Articles in Materials Science and Engineering

Optical And Electrical Characterization Of Bulk Grown Indium-Gallium-Arsenide Alloys, Austin C. Bergstrom Mar 2010

Optical And Electrical Characterization Of Bulk Grown Indium-Gallium-Arsenide Alloys, Austin C. Bergstrom

Theses and Dissertations

Advances in crystal growth techniques have allowed increased quality in growth of bulk ternary InxGa1-xAs. Here, the optical and electrical properties of samples grown through the vertical Bridgman (or multi-component zone melting growth) method have been investigated through photoluminescence spectroscopy and Hall effect measurements. Indium mole fractions varied from 0.75 for 1. Hall effect measurements at temperatures ranging from 10 to 300 K revealed moderate n-type doping with carrier concentrations ranging from 1.5 to 9.6×1016 cm-3 at 10 to 15 K. Carriers from deep donor levels became appreciable between 50 and 100 K. Hall …


Characterization And Measurement Of Passive And Active Metamaterial Devices, Christopher A. Lundell Mar 2010

Characterization And Measurement Of Passive And Active Metamaterial Devices, Christopher A. Lundell

Theses and Dissertations

This document addresses two major obstacles facing metamaterial development: uncertainty in the characterization of electromagnetic field behavior in metamaterial structures and the relatively small operational bandwidth of metamaterial structures. To address the first obstacle, a new method to characterize electromagnetic field behavior in a metamaterial is presented. This new method is a bistatic radar cross section (RCS) measurement technique. RCS measurements are well-suited to measuring bulk metamaterial samples because they show frequency dependence of scattering angles and offer common postprocessing techniques that can be useful for visualizing results. To address the second obstacle, this document characterizes the effectiveness of an …