Stress tunable dynamic susceptibility of stripe domains in flexible FeGa films

Understanding the dynamic magnetic susceptibility of stripe domain structures is crucial for developing high-frequency magnetic microwave devices. Stripe domains are commonly observed in soft magnetic films that exhibit perpendicular anisotropy. The unique distribution of magnetic moments in the stripe domains enhances their performance at high frequencies. Integrating stripe domain structures into high-frequency magnetic devices offers numerous advantages and has become a focal point for researchers. However, studies on the performance of stress-controlled stripe domains are limited. In this study, the static and dynamic magnetism of a stripe domain structure in flexible stress-tuned FeGa films was investigated using micromagnetic simulations. The numerical results indicate that perpendicular excitation of the stripe domain produces two resonance modes: Bloch domain-wall resonance and domain-core resonance, which are in phase. The applied compressive or tensile stresses significantly regulate the resonance frequency of the FeGa films. As stress-induced anisotropy transitions from positive to negative (from maximum tensile stress to maximum compressive stress), the two resonance modes shift from low to high frequencies, thereby increasing the resonance frequency of the stripe domain. These findings are anticipated to pave the way for high-frequency magnetic devices that utilize magnetic nanostructures.