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Please use this identifier to cite or link to this item: http://hdl.handle.net/123456789/1242

Authors: Tefera, Melaku
Advisors: Dr. Mulugeta Bekele
Copyright: 2003
Date Added: 25-May-2008
Publisher: Addis Ababa university
Abstract: Abstract In bistable systems the transition kinetics between two locally stable states can be altered by heating locally one of the stable states (using blow-torch). As a model for diffusion in a non-homogeneous medium, we consider the hopping model. The kinetic aspect of blowtorch effect is investigated for a model double-well potential with localized heating. That is, we analyze the relaxation behavior of a bistable system when the background temperature profile is non-homogeneous. Using Brinkman’s method, we derive the general and analytic expressions for the escape and equilibration rates of the system as a function of the strength, width, and the position of the hot locality, the barrier height and the pit potential of traps for the model that we consider. Our result shows that the presence of the hot locality enhances the escape rate from the well where it is placed and retards the escape rate from the other well. Our work also shows a remarkable result in relation to the position of the hot locality in that placing the hot locality mid way between the top and bottom of the well has the largest enhancing effect on the escape rate from the hot zone than any other position. This result is similar to the work of Solomon Fekade and Mulugeta Bekele for the case of Landauer’s heated pipe model[1]. Moreover, the escape and equilibration rates of the system become decreasing functions of the barrier height and the pit potential of traps.
Description: A Thesis Submitted to the School of Graduate Studies Addis Ababa University In Partial Fulfillment of the Requirement for the Degree of Master of Science in Physics
URI: http://hdl.handle.net/123456789/1242
Appears in:Thesis - Physics

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