Shaped pulses can be used for uniform spin-1 excitation. The effects of the pulses on spin-1 excitation is seen as distortion of two types: phase distortions and amplitude distortions. By reducing the distortions a spin-1 excitation becomes more uniform. In the case of time-symmetric shaped pulses, spin-1 excitation is free of phase distortions. The spin-1 excitation in that case can be made uniform over a larger frequency bandwidth. The number of possible shaped pulses is so large that a computer-aided search is needed to find the desirable shaped pulses. A theoretical analysis is used to find the connection between a shaped pulse and the corresponding spin-1 excitation. The theoretical analysis in density matrix formalism gives the spin-1 excitation in closed-form expressions that are too complicated. In such a case the connection between a shpaed pulse and spin-1 excitation is not straightforward. A brute-force search for a desirable shaped pulse can consume too much computer time and thus time the scope of the search. By using the formalism of quaternions in the theoretical analysis, spin-1 excitation is presented in simple closed form expressions. It is then shown tht if the choice is limited to time-symmetric shaped pulses then these closed form expressions become much simpler. It is also shown that a spin-1 excitation is free of phase distortions in that case. These simple closed form expressions can be used as the building blocks of a much more concise program code for the computer aided search. As a result a computer aided search for a desirable shaped pulse becomes much faster in speed and larger in scope. More shaped pulses for improved spin-1 can be found. / xiii, 99 leaves : ill. ; 28 cm.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:ALU.w.uleth.ca/dspace#10133/71 |
Date | January 1998 |
Creators | Habot, Simon, University of Lethbridge. Faculty of Arts and Science |
Contributors | Siminovitch, David |
Publisher | Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 1998, Arts and Science, Department of Physics |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | en_US |
Detected Language | English |
Type | Thesis |
Relation | Thesis (University of Lethbridge. Faculty of Arts and Science) |
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