掺Sc钇铁石榴石(YIG)铁氧体电磁参数和吸波性能

Electromagnetic parameters and wave absorption properties of Sc-doped yttrium iron garnet(YIG)ferrites

利用固相反应方法制备了Y_(3)Sc_(1.05)Fe_(3.95)O_(12)钇铁石榴石铁氧体(YIG)并测量得到其磁导率和介电常数谱。根据电磁参数分别使用λ/4干涉相消机制和磁损耗机制计算得到吸波体厚度随频率的变化。发现这两种机理得到的理论厚度都与实际厚度存在偏离,使用界面反射的相位关系,得到在211 MHz处存在λ/4干涉相消机制形成的反射损耗峰,进一步得出两种机理所形成的反射损耗峰。通过电磁参数对1~1000 MHz范围内的吸波性能进行设计,使吸波体厚度为6 mm时具有−10 dB以下吸收效能,吸收带宽为30 MHz(420~450 MHz)。根据界面反射模型对吸收带宽进行讨论,理论计算结果与实测结果吻合。

Y_(3)Sc_(1.05)Fe_(3.95)O_(12) ferrite(YIG)was prepared by solid-phase reaction method and its magnetic permeability and dielectric constant spectra were measured.The thickness variation with frequency was calculated based on the electromagnetic parameters using theλ/4 interference phase extinction mechanism and the magnetic loss mechanism,respectively.It is found that the theoretical thicknesses obtained by both mechanisms were found to deviate from the actual thicknesses,and the reflection loss peaks formed by theλ/4 interference phase extinction mechanism were obtained at 211 MHz using the phase relationship of the face reflections,and the reflection loss peaks formed by both mechanisms were further derived.We report the absorption performance in the range of 1 to 1000 MHz is designed by the electromagnetic parameters of YIG,so that the absorber thickness of 6 mm has the absorption efficiency below–10 dB and the absorption bandwidth is 30 MHz(420 to 450 MHz).The absorption bandwidth was discussed according to the face reflection model and the theoretical calculations agree with the experimental values.