Analysis of noise spectral density and coherence resonance phenomena in mixed hysteretic systems driven by noise

In this article, the authors focus on the characterization of mixed clockwise-counterclockwise hysteretic system response to white and colored noise and prove that coherence resonance can be identified in such systems driven solely by noise . Mixed hysteretic behavior have been observed experimentally in several magnetic multi-layer and superlattices materials with antiferromagnetic interlayer coupling and positive exchange bias. Several mixed and hybrid hysteretic models based on the superposition of standard counter-clockwise hysteretic models, such as Preisach and Jiles-Atherton, and their newly developed clockwise variants have been proposed to describe this anomalous magnetic behavior. Here, we consider the mixed Preisach model obtained by linear (convex) combination of classical counter-clockwise Preisach model and the clockwise Preisach model first developed by Mayergoyz and Andrei to describe nonlinear diffusion of electromagnetic fields in conducting magnetic media with abrupt magnetic transitions. Various types of noise inputs are considered, such as white Gaussian noise, Ornstein-Uhlenbeck noise and pink Gaussian noise, and the output power spectral densities are computed, analyzed and compared for various input parameters.