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The magnetic properties of various samples were investigated through vibrating sample magnetometer, electron spin resonance (ESR), and vector network analyzer ferromagnetic resonance (VNA-FMR) techniques, respectively. The corresponding saturation magnetization $4\pi M_{s}$ and in-plane magnetic anisotropy field $H_{k}$ of those different films were estimated by the three methods. A comparative investigation of the three techniques, especially for ESR and VNA-FMR, on the estimation of $4\pi M_{s}$ and $H_{k}$ was analyzed systematically. The influence of omitted $H_{k}$ on the data of $4\pi M_{s}$ and $H_{k}$ was also studied. The results provide a quite clear conclusion for the measurements of $4\pi M_{s}$ and $H_{\mathbf {k}}$ in different conditions.

Nanowire/Permalloy (Ni 80 Fe 20 ) composite films were fabricated by combined electrospinning and sputtering. The magnetic properties of the composite films are isotropic in-plane. Stripe domains were characterized by magnetic force microscopy and vector-network-analyzer ferromagnetic resonance. Compared with pure Permalloy films with distinct stripe domains, the composite films have weaker stripe domains but better soft magnetic properties. The coercivity and dynamic anisotropy fields are 47 Oe and 73 Oe, respectively, for pure Permalloy, decreasing to 23 Oe and 67 Oe, respectively, for the Fe-Ni nanowire/Permalloy composite film. Composite films provide new insight on the improvement of the soft magnetic properties of magnetic films.

Stripe domains in magnetic thin films as well as many of its associated intriguing behaviors has been receiving much attention from researchers for a long time [1]. Stripe domains often present a pseudo-uniaxial anisotropy that aligns along the stripe direction, whose axis can be re-aligned by the application of a sufficiently large in-plane magnetic field [2]. Thus, this pseudo-uniaxial anisot-ropy can be regarded as a rotatable anisotropy that rotates along with the applied field. The magnitude of this stripe domain induced anisotropy can be comparable or even much higher than that of uniaxial anisotropy induced by sputtering deposition in a magnetic field, thus this provide a powerful method to tune ferromagnetic resonance frequencies for high frequency microwave applications [3]. In addition, the omni-directional characteristic of rotatable anisotropy makes it highly flexible for applications. FeNi alloys have a great attention for more than six decades as a consequence of their highly sought-after magnetic characteristics in the development of magnetic data storage systems [4]. In addition, FeNi film is the typical stripe domains structure when the film exceeds “transcritical” state [5], which can be controlled by the film thickness. Significantly, the state of magnetic moment magnetization is crucial adjective status for the pseudo-uniaxial anisotropy and stripe domains.