19 resultados para Collimators (Optical instrument)
Resumo:
Please consult the paper edition of this thesis to read. It is available on the 5th Floor of the Library at Call Number: Z 9999 E38 D56 1992
Resumo:
This thesis reports on the optical properties of the dilute magnetic semiconductors, Sb1.97 V 0.03 Te3 and Sb1.94Cr0.06Te3, along with the parent compound Sb2Te3' These materials develop a ferromagnetic state at low temperature with Curie temperatures of 22 K and 16 K respectively. All three samples were oriented such that the electric field vector of the light was perpendicular to the c-axis. The reflectance profile of these samples in the mid-infrared (500 to 3000 cm-1) shows a pronounced plasma edge which retracts with decreasing temperature. The far-infrared region of these samples exhibits a phonon at ~ 60 cm-1 which softens as temperature decreases. Kramers-Kronig analysis and a Drude-Lorentz model were employed to determine the optical constants of the bulk samples. The real part of the optical conductivity is shown to consist of intraband contributions at frequencies below the energy gap (~0.26 eV) and interband contributions at frequencies above the energy gap. The temperature dependence of the scattering rate show that a mix of phonon and impurity scattering are present, while the signature of traditional spin disorder (magnetic) scattering was difficult to confirm.
Resumo:
Public Instrument of Protest (1 double-sided handwritten page) by William W. Gillvery and the North West Company against Angus W. Gillis for breaking his agreement with the company, March 26, 1800.
Resumo:
Instrument of protest from Edward Barrori Palmer, Notary Public of Oakville regarding a protest by Samuel Sutherland, Master of the schooner Elizabeth and Charles McEacherin, mate. The schooner belonged to the Port of Niagara. It set sail from Port Credit to the Port of Niagara. On the 15th day of May there was a violent storm. On the 16th day of May, part of the deck and cargo consisting of lumber went overboard. The mainsail was lost and the jib was split due to the wind. All losses and damages should be borne by the merchants and whomever else it concerned and not by or through the insufficiency of the schooner of neglect by the officers and mariners. This is a 2 ½ page handwritten document, May 16, 1837.