(Li_(0.5)F_(0.5))_(0.7-y)Zn_(0.3)Co_yFe_2O_4铁氧体铁磁共振的研究

Ferromagnetic resonance study of (Li_(0.5)F_(0.5))_(0.7-y)Zn_(0.3)Co_yFe_2O_4 ferrites system

锂系铁氧体是一类人们广泛关注的毫米波铁氧体材料 ,离子代换可以大大改善材料的性能。本文在 L i-Zn铁氧体 ( L i0 .5F0 .5) 0 .7Zn0 .3Fe2 O4 基础上 ,用 Co2 +离子代换其中的 ( Li+Fe3+) 0 .5离子 ,研究了 ( Li0 .5Fe0 .5) 0 .7- y Zn0 .3Coy Fe2 O4 ( y=0 .0 0 ;0 .0 0 5;0 .0 1 ;0 .0 2 ;0 .0 3 )铁氧体室温铁磁共振效应 ,实验结果表明 ,铁磁共振线宽与 Co2 +离子的代换量、烧结温度和工作频率有密切关系。当 Co2 +离子含量 y <0 .0 2 ,铁磁共振线宽μ0 ΔH随 Co2 +离子含量的增加而减小 ,在 y =0 .0 2处得到最小铁磁共振线宽。在烧结温度 Ts=1 1 0 0℃左右可得到较小的铁磁共振线宽。当工作频率 f >8GHz,铁磁共振线宽μ0 ΔH∝ f。

Li system ferrites are kinds of millimetre\|wave material concerned extensively, the substitution of ions would improve effectively the properties of materals. Based on(Li\-\{0.5\}F\-\{0.5\})\-\{0.7\}Zn\-\{0.3\}Fe\-2O\-4 ferrite, Co ion substitutes for (LiFe), and then the effect of room\|tempenature ferromagretic resonance (FMR) of (Li\-\{0.5\}Fe\-\{0.5\})\-\{0.7-\%y\%\}Zn\-\{0.3\}Co\-\{\%y\%\}Fe\-2O\-4(\%y\%=0.00;0.005;0.01;0.02;0.3) ferrites system is studied. The experimental results show that the FMR line\|widths have tight relation to the amount of Co ion, the sintered temperature and work frequency. The FMR line\|width is decreased with the increase of Co ion substitution, when the Co ion subsitution \$y\$<0.02, and the FMR line\|width is min. at \$y\$=0.02. The less FMR line\|width would have been gotten under the sintered temperature \$T\-s\$=\{1 100℃\}. The FMR line\|width \$μ\-0\%Δ\%H∝f\$ under the work frequency \$f\$>8GHz.