A. G. U. Perera and S. G. Matsik
Department of Physics and Astronomy, Georgia State University, Atlanta, GA 30303ABSTRACT
We report the experimental observation and modelling results confirming the transition to periodicity from chaotic(although still deterministic) spontaneous firing patterns for Silicon p-i-n structures at 4.2K controlled by a constant current source. These patterns are determined by measuring the interpulse time interval (IPTI) between pulses. In contrast to a naive view, which suggests periodic patterns under current conservation, we see a rich spectrum of behavior due the space charge effects, when the control parameter(drive current)is varied. In particular, a bi-modal pattern is found in which the IPTIs occur in two distinct groups rather than as a single continous distribution. Nonlinear dynamics analysis tools as well as a statistical approach(i.e. Markov process) confirm the change from chaotic to periodic behavior as the control parameter increases. A theoretical model based on device physics for the buildup of space charge in the i-region of the diode giving insight into semiconductor device fabrication is developed to explain the bi-modal pulsing behavior observed. This can be used to enhance our understanding of various pulsing device applications, including IR detectors, processors and neural networks. © 1995 Elsevier Science B. V.
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