Wasp-waist and pot belly hysteresis loops have been observed in many materials. When only the major loop is reported, the results are insufficient to establish which processes are involved. We present two models for wasp waist materials that produce virtually indistinguishable major loops, but show the first order reversal curves can be used to separate the effects. In the simplest model, we take a soft magnetic material and a hard material and exchange couple them. When the exchange is positive, the loop is conventional. However, for negative (antiferromagnetic) exchange, the wasp waist loop is obtained. Negative coupling of two materials with different switching fielf distributions leads to pot bellied loops.
Journal of Applied Physics
pot belly hysteresis, Preisach, wasp waist
and Della, E.
Analysis of Wasp Waist Hysteresis Loops, Journal of Applied Physics
(Accessed December 7, 2023)