Yasukawa Yukiko, Nozawa Kouhei, Tiittanen Taneli, Karppinen Maarit, Lindén Johan, Shirsath Sagar E, Yabukami Shin
Department of Electrical and Electronic Engineering, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba, 275-0016, Japan.
Graduate School of Engineering, Tohoku University, Building No. 2, 6-6-05 Aoba Aza Aramaki, Aoba, Sendai, Miyagi, 980-8579, Japan.
Sci Rep. 2021 Jan 12;11(1):614. doi: 10.1038/s41598-020-79768-z.
We have fabricated a high quality magnetic NiZnFeO ferrite powder/polymer composite sheet consisting of common and environmentally friendly elements only. The sheet was then tested for its dynamic permeability by irradiating with electromagnetic waves with frequencies up to 50 GHz. Two different originally developed methods were used for the high-frequency permeability measurements, a short-circuited microstrip line method and a microstrip line-probe method. It is challenging to measure the dynamic permeability of magnetic thin films/sheets beyond 10 GHz because of the low response signal from these materials. However, the two methods produced essentially equivalent results. In the frequency dependent permeability profile, the maximum position of the profile, [Formula: see text], shifted towards higher frequencies upon increasing an applied (strong) static external magnetic field, [Formula: see text]. A linear relationship between [Formula: see text] and [Formula: see text] for the entire range of [Formula: see text] was observed even at small [Formula: see text]. In general, the spinel-structured Ni-based ferrites exhibit low magnetic anisotropy, but the present sample showed a uniaxial-anisotropic behavior in the parallel direction of the sheet. Our NiZnFeO powder/polymer composite sheet thus exhibits high performance at GHz frequencies, and should be applicable e.g. as an anisotropic electromagnetic wave-interference material.
我们制备了一种仅由常见且环保的元素组成的高质量磁性镍锌铁氧体粉末/聚合物复合片材。然后，通过用频率高达50 GHz的电磁波照射该片材来测试其动态磁导率。两种最初开发的不同方法被用于高频磁导率测量，即短路微带线法和微带线探针法。由于这些材料的响应信号较低，测量超过10 GHz的磁性薄膜/片材的动态磁导率具有挑战性。然而，这两种方法产生的结果基本相同。在频率相关的磁导率分布图中，分布图的最大值位置，[公式：见正文]，随着施加的（强）静态外部磁场，[公式：见正文]的增加而向更高频率移动。即使在小的[公式：见正文]时，在整个[公式：见正文]范围内也观察到[公式：见正文]和[公式：见正文]之间的线性关系。一般来说，尖晶石结构的镍基铁氧体表现出低磁各向异性，但本样品在片材的平行方向上表现出单轴各向异性行为。因此，我们的镍锌铁氧体粉末/聚合物复合片材在GHz频率下表现出高性能，并且应该适用于例如作为各向异性电磁波干扰材料。
