Applied and Interdisciplinary Mathematics Seminar

University of Michigan

Fall 2005
Friday, 18 November, 3:10-4:00pm, 1084 East Hall

Coupling-Induced Cooperative Behavior in Overdamped Nonlinear (Bistable) Dynamic Systems

Adi R. Bulsara

Space and Naval Warfare Systems Center
San Diego, CA


Abstract

We discuss the emergence of oscillations in overdamped undriven nonlinear dynamic systems subject to carefully crafted coupling schemes and operating conditions. Here we summarize results for a system of N=3 coupled ferromagnetic cores, the underpinning of a "coupled-core fluxgate magnetometer" (CCFM); the oscillatory behaviour is triggered when the coupling constant exceeds a threshold value (bifurcation point), and the oscillation frequency exhibits a characteristic scaling behaviour with the magnitude of the deviation of the coupling constant from its threshold value, as well as with an external "target" dc magnetic flux signal. We also present the first (numerical) results from our investigations into the large N case where background noise is seen to mediate interesting spatio-temporal cooperative behavior.