磁性Salisbury屏的高频响应

研究了利用磁性薄膜构造Salisbury屏的可能性及其在微波频段的反射率频率特性.结果表明，利用铁磁性材料在铁磁共振频率附近磁化率具有χ″>χ′的特性，可以构造出对电磁波有良好吸收性能的磁性Salisbury屏.通过对铁磁材料高频磁谱物理机理的分析后指出，具有弛豫型共振磁谱的铁磁材料可以构造出薄膜型Salisbury屏，其厚度为微米甚至亚微米量级.反射率的频率特性与磁性材料的特征阻抗z-r有关，它取决于铁磁共振频率和静态磁化率.反射率的频率响应显示磁性薄膜Salisbury屏具有较宽的吸收带宽. 关键词： 磁性Salisbury屏 反射率 频带响应 磁性薄膜

Magnetic Salisbury screen and its high-frequency response

We have studied the possibility of constructing magnetic Salisbury screen, and the frequency response of reflectivity of the screen in microwave frequency range. We have found that magnetic Salisbury screen has a lower reflectivity when magnetic susceptibility satisfies χ″χ′. If the frequency response of magnetic susceptibility is in the relax type of domain wall resonance, we could make film type Salisbury screen, in which the thickness of the screen may be in the order of micrometer or even sub micrometer. The reflectivity of the screen depends on the characteristic impedance zr of the magnetic film that is determined by ferromagnetic resonant frequency and susceptibility under a static field. The frequency response of reflectivity shows that the magnetic film Salisburyscreen has a broadband frequency range for absorbing microwaves well.