Microwave and Millimeter Wave Ferromagnetic Absorption of Nanoferrites
Microwave and Millimeter Wave Ferromagnetic Absorption of Nanoferrites
复制标题
纳米铁氧体的微波和毫米波铁磁吸收
DOI：
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发表时间：
2012
影响因子：
2.1
通讯作者：
M. Afsar
中科院分区：
文献类型：
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作者：
L. Chao;A. Sharma;M. Afsar
已经在宽的微波和毫米波频率范围内研究了几种市售纳米铁氧体的复介电常数和磁导率。研究了不同晶格结构的钡、锶、铜、锌、镍取代氧化铁纳米粉体。采用矢量网络分析仪的基于透射-反射的波导内技术用于确定两个微波波段（18-40 GHz）中每个样品的散射参数。利用返波振荡器激励的自由空间准光学光谱仪获得了毫米波频率范围（30-120 GHz）的透射谱。在毫米波频段观察到六角晶系钡铁氧体和锶铁氧体的较宽而尖锐的铁磁共振。与微米级和实心六方晶系铁氧体相比，纳米级六方晶系铁氧体粉末材料的铁磁共振峰向低频移动。对这些六方晶系铁氧体进行X射线衍射测量，以了解磁性行为和结构。
Complex dielectric permittivity and magnetic permeability of several commercially available nanoferrites have been studied over a broad microwave and millimeter wave frequency range. Nano-sized barium, strontium, copper, zinc, nickel substituted iron oxide powders with different lattice structures are investigated. A transmission-reflection based in-waveguide technique that employs a vector network analyzer was used to determine the scattering parameters for each sample in two microwave bands (18-40 GHz). A free space quasi-optical spectrometer energized by backward wave oscillators was used to acquire the transmittance spectra in the millimeter wave frequency range (30-120 GHz). Relatively broad and sharp ferromagnetic resonance of hexagonal barium ferrite and strontium ferrite are observed in millimeter wave frequency range. The ferromagnetic resonance peak for nano-sized hexagonal ferrite powder material moves to lower frequencies compared to micro-sized and solid hexagonal ferrites. An X-ray diffraction measurement is performed on these hexagonal ferrites to understand the magnetic behavior and the structure.