Observation of recoil magnetization curves outside the major loop in Co, Fe, and Ni films

We report a peculiar magnetization reversal observed in magnetron-sputtered Co, Fe, and Ni films. We found that some recoil (minor) magnetization curves lie entirely and way outside the major loop, a phenomenon referred to here as a recoil-curve overshoot. The greatly enhanced recoil curve's remanence and coercivity result in an up to 2.5-fold increase of loop's area. The model of pairs of exchange-coupled grains with misaligned anisotropy axes reproduces, in a very good agreement with the experiment, all key features of the recoil-curve overshoot as well as the kink that some major loops present before saturation. The disclosed features of the ferromagnetic hysteresis provide further insights into this important classical phenomenon.

Automated summary

In this study, a peculiar magnetization reversal phenomenon, known as recoil-curve overshoot, was observed in magnetron-sputtered Co, Fe, and Ni films. The greatly enhanced recoil curve's remanence and coercivity led to a significant increase in loop's area. A model involving pairs of exchange-coupled grains with misaligned anisotropy axes successfully reproduced the key features of the recoil-curve overshoot and the kink in some major loops before saturation, providing further insights into the classical ferromagnetic hysteresis.