Coupled overdamped bistable systems with applications to sensor devices

Abstract

Theoretical and experimental works have shown that coupling similar overdamped bistable systems can lead, under certain conditions that depend on the topology of connections and the number of units, to self-induced large-amplitude oscillations that emerge through a global bifurcation of heteroclinic connections between saddle-node equilibria. We have exploited this fundamental feature to model, design, and fabricate a new generation of highly-sensitive, low-powered, sensor devices, mainly detectors of magnetic- and electric-fields. In this article we review the fundamental principles and methods behind this new paradigm. These principles are device-independent so they can be readily adapted to a wide range of sensors, such as acoustic and gyroscopic sensors among many types. In this manuscript we describe the design and fabrication of a new class of highly-sensitive fluxgate- and electric-field magnetometers as a case study to review basic ideas and methods.