A Bistable Microelectronic Circuit for Sensing Extremely Low Electric Field

摘要

Bistable systems are prevalently found in many sensor systems. Recently, we have explored unidirectionally coupled overdamped bistable systems that admit self-sustained oscillations when the coupling parameter is swept through the critical points of bifurcations. Complex behaviors emerge, in addition, from these relatively simple coupled systems when an external signal ac or dc is applied uniformly to all the elements in the array. In particular, we have demonstrated this emergent behavior for a coupled system comprised of mean-field hysteretic elements describing a single-domain ferromagnetic sample. The results are being used to develop extremely sensitive magnetic sensors capable of resolving field changes as low as 150pT by observing the changes in the oscillation characteristics of the coupled sensors. In this paper, we explore the underlying dynamics of a coupled bistable system realized by coupling microelectronic circuits, which belong to the same class of dynamics as the aforementioned ferromagnetic system, with the nonlinear features and coupling terms modeled by hyperbolic tangent nonlinearities; these nonlinearities stem from the operational transconductance amplifiers used in constructing the microcircuits. The emergent behavior is being applied to develop an extremely sensitive electric-field sensor.