第8期 徐芳等：频率可调磁感应波器件的微波透射性能 。1037。 24(a 0-160kAm 12.0(b) 0 --240 kA.ml 2 -△-320kAmr -+=400kAml 11.5 ★-480kAm 6 ◆ -8 -10 10.5 -12 -14 10.0■ 9.510.010.511.011.512.012.513.0 1.52.02.53.03.54.04.5 f/GHz H/(10'A.ml) 图6()实验得到的双层铁氧体复合结构的透射曲线：(b)特征频率随偏置磁场的变化 Fig 6 (a)Measured transmission pecra of the bilayened ferrite shbss (b)change of chanacteristic freqency with the strength of lias magnectic field [2 Houck AA.Brock J B.Chuang I L.Experimental observations of 0 mm a left-handed material that obeys Snell s law.Phys Rev Lett 2003.90:137401 [3 Seddon N.Bearpark T.Observation of the inverse Doppler ef- fed.Science,2003,302:1537 [4 Luo C Y,Ibanscu M,Johnson S G,et al.Cerankov radiation in photoric erystals.Science,2003.299:368 [5 Pendry J B.Negative mefraction makes a perfect lens.Phys Rev L41,2000,85:3966 0.9 1.0 1.1 12 [6 Fang N.Lee H.Sun C.et al.Sulrdiffraction limited optical fif imaging with a silver supedens Scienc,2005,30&534 [7 Merg F Y.Wu Q.Jin B S.et al.Numerical verification of the NIR 图7d值不同时微波器件的透射性能 feat ures for 2-D isot ropic LHM.Acta Phys Sin,2006,55:4514 Fig.7 Transmission propertie of the microw ave devices with dif (孟繁义，吴群，金博识.等.二维各向同性异向介质负折射特 ferent d values 性仿真验证.物理学报.2006.55：4514) 3结论 L图1 MaslovsiS.TretyakovS,Alitalo P.Near-field enhancement and imaging in double planar polariton-resonant structures.J Appl 本文结合理论分析、仿真计算与实验测试，研究 Phs,2004,96:1293 了由双层磁化铁氧体构成的磁感应波器件的微波透 [9 Marques R.M esa F.Medina F.Near-field enhanced imaging by a magnet ized femite shh.Appl Phys Lett,2005,86:023505 射性能.在偏置磁场和微波场的共同作用下，平行 [10 Freire M J,M arges R.Planar magnetoinductive lens for three 放置的两铁氧体发生铁磁共振，间隙处表面波共振 dimensional subw avelength imaging.Appl Phys Lett,2005, 模强烈耦合，磁场显著增强，产生磁感应波透过样 86:182505 品，由此导致在铁磁共振产生的微波禁带频率范围 [11]Freire M J,Marues R.Optimizing the magnetoinductive lens: 内出现一明显的通带，该通带具有很好的场致频率 improwement limits,and possible applications.J Appl Phys, 2008.103:013115 可调性，其中心频率随偏置磁场的增强而单调上升， [12 Sydomuk 0,Shamorin M.Radkovskaya A.et al.Mechanism of 良好的频率可调性可以进一步丰富磁感应波器件的 subw aveength imaging with bilayerd magnetic metamaterials 功能，扩展其应用领域.这种可调磁感应波器件可 theroy and experiment.JApp/Phys.2007.101:073903 用于磁共振成像系统，作为磁场探测器，提供更高速 13]Ai F,Bai Y,Xu F,et al.Research on the tunable left-handed 更精确的实时成像信息.该复合结构的微波特性同 pmperties of split-ring resonators with ferrite substrate.Acta 时受其结构参数的影响.随着两铁氧体间距的增 Ph3Sim,2008.57:4189 (艾芬，白洋，徐芳，等.基于铁氧体基板的开口谐振环的可调 加，耦合作用减弱，透射通带的半高宽逐渐降低、损 微波左手特性研究.物理学报.2008,57：4189) 耗增加. [14 Chen J W.Zhang B S.Targ DM,et al.Possible existence of a new type of left-handed materials in coupled fermomagnetic bilay- 参考文献 er films.J Magn Magn Mater,2006.302:368 [1]Veselago V G.The electrodynamics of substance with simultane- 15]Syms P RA,Young I R.Solymar L Low-bss magneto-induc- ously negative values of e and #Sov Phys Usp.1968.10:509 tive waveguides.J Phys D.2006.39 3945图 6 ( a) 实验得到的双层铁氧体复合结构的透射曲线;( b) 特征频率随偏置磁场的变化 Fig.6 ( a) Measured transmission spectra of the bilayered f errite slabs;( b) change of charact eristic frequency with the strength of bias magnetic field 图 7 d 值不同时微波器件的透射性能 Fig.7 Transmission properties of the mi crow ave devices w ith dif￾ferent d values 3 结论 本文结合理论分析、仿真计算与实验测试, 研究 了由双层磁化铁氧体构成的磁感应波器件的微波透 射性能 .在偏置磁场和微波场的共同作用下, 平行 放置的两铁氧体发生铁磁共振, 间隙处表面波共振 模强烈耦合, 磁场显著增强, 产生磁感应波透过样 品, 由此导致在铁磁共振产生的微波禁带频率范围 内出现一明显的通带 .该通带具有很好的场致频率 可调性, 其中心频率随偏置磁场的增强而单调上升 . 良好的频率可调性可以进一步丰富磁感应波器件的 功能, 扩展其应用领域 .这种可调磁感应波器件可 用于磁共振成像系统, 作为磁场探测器, 提供更高速 更精确的实时成像信息.该复合结构的微波特性同 时受其结构参数的影响 .随着两铁氧体间距的增 加, 耦合作用减弱, 透射通带的半高宽逐渐降低 、损 耗增加. 参 考 文 献 [ 1] Veselago V G .The electrodynami cs of substance with simultane￾ously negative values of εand μ.Sov Phys Usp , 1968, 10:509 [ 2] Houck A A, Brock J B, Chuang I L.Experimental observations of a left-handed material that obeys Snell' s law .Phys Rev Lett , 2003, 90:137401 [ 3] Seddon N, Bearpark T .Observation of the inverse Doppler ef￾f ect .Sci ence, 2003, 302:1537 [ 4] Luo C Y, Ibanscu M , Johnson S G, et al.Cerankov radiation in photoni c cryst als.S cience, 2003, 299:368 [ 5] Pendry J B .Negative refraction makes a perfect lens.Phys Rev Lett, 2000, 85:3966 [ 6] Fang N, Lee H, Sun C , et al.Sub-diffraction-limited optical imaging w ith a silver superlens.Science, 2005, 308:534 [ 7] Meng F Y, Wu Q, Jin B S, et al.Numerical verification of the NIR features f or 2-D isotropic LHM.Acta Phys Sin, 2006, 55:4514 ( 孟繁义, 吴群, 金博识, 等.二维各向同性异向介质负折射特 性仿真验证.物理学报, 2006, 55:4514) [ 8] Maslovski S , Tretyakov S , Alit alo P.Near-field enhancement and imaging in double planar polarit on-resonant structures.J App l Phys, 2004, 96:1293 [ 9] Marqués R, M esa F, Medina F .Near-field enhanced imaging by a magnetized ferrit e slab.A ppl Phys Lett, 2005, 86:023505 [ 10] Freire M J, M arqué s R.Planar magnetoinductive lens f or th ree￾dimensional subw avelength imaging .Ap pl Phys Lett, 2005, 86:182505 [ 11] Freire M J, Marqués R.Optimizing the magnet oinductive lens: improvement, limits, and possible appli cations.J Appl Phys, 2008, 103:013115 [ 12] Sydoruk O, S hamonin M, Radkovskaya A, et al.Mechanism of subw avelength imaging with bilayerd magnetic metamaterials: theroy and experiment .J App l Phys, 2007, 101:073903 [ 13] Ai F, Bai Y, Xu F, et al.Research on the tunable left-handed properties of split-ring resonators w ith ferrit e substrate .Acta Phys S in , 2008, 57:4189 ( 艾芬, 白洋, 徐芳, 等.基于铁氧体基板的开口谐振环的可调 微波左手特性研究.物理学报, 2008, 57:4189) [ 14] Chen J W, Zhang B S , Tang D M, et al.Possible exist ence of a new t ype of left-handed mat erials in coupled ferromagnetic bilay￾er films.J Magn Magn Mater, 2006, 302:368 [ 15] Syms P R A, Young I R, Solymar L.Low-loss magneto-induc￾tive waveguides.J Phys D, 2006, 39:3945 第 8 期 徐 芳等:频率可调磁感应波器件的微波透射性能 · 1037 ·