共查询到19条相似文献,搜索用时 140 毫秒
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由磁光介质(M)和电介质(G)周期性排列构成的磁光光子晶体会出现很强的光 局域性,最近用它来实现磁光隔离器引起人们广泛的兴趣.给出了一种可用于计算 偏振光在各向异性介质传播问题的传输矩阵方法.并用该方法计算了对称多缺陷结构磁光多 层膜隔离器的光学性质,发现随着缺陷数目的增多,旋转角及透过率的频谱响应得到改善. 当缺陷增加到一定数目时,不需要额外的反射层即可实现反射型磁光隔离器的要求.
关键词:
光隔离器
磁光效应
多层膜
光子晶体 相似文献
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由于一维磁光子晶体能同时展示出很好的光透射率和法拉第旋转,故可用于实现小尺度的磁光隔离器。采用传输矩阵法研究了由磁光膜(Bi∶YIG)和电介质膜(Ta2O5,SiO2)构成的一维磁光子晶体,分别讨论了在垂直入射和斜入射条件下的法拉第效应,并给出了几种可行性结构,对磁光隔离器件的进一步改进设计具有一定的参考价值。 相似文献
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采用4×4传输矩阵法研究了两种结构一维磁光子晶体的光隔离特性.结构一在外加磁场与光路光轴方向呈52.0°时,用7.96μm的总厚度在中心波长附近0.95nm范围内实现了光隔离,在此范围之内法拉第旋转角和透射率分别在45°~50.65°和97.01%~99.96%之间波动,结构仅包含43层光学薄膜,易于实际制备;结构二在外加磁场与光路光轴方向呈32.7°时,用11.54μm的总厚度在中心波长附近0.85nm范围内实现了光隔离,在此范围之内法拉第旋转角和透射率分别在45°~48.55°和98.85%~100%之间波动,结构包含73层光学薄膜,与结构一相比,该结构具有更高的透射率和更平坦的光谱.用这两种结构的一维磁光子晶体代替目前商用磁光隔离器中的块状磁光介质,可实现磁光隔离器的集成化. 相似文献
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基于平面波展开法,设计三层一维光子晶体横磁场模结构,改变三层介质厚度和介质折射率的大小,应用MATLAB语言进行仿真计算,在一维光子晶体三层介质厚度值为0.4、0.05μm和0.05μm,折射率为1、3N和12N时形成一维光子晶体带隙宽度最宽为0.2694Hz.研究结论为一维光子晶体器件的设计提供理论依据. 相似文献
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A. Lesuffleur M. Vanwolleghem P. Gogol B. Bartenlian P. Beauvillain J. Harmle L. Lagae J. Pistora K. Postava S. Visnovsky R. Wirix-Speetjens 《Journal of magnetism and magnetic materials》2006
In order to optimize a 1.3 μm integrated optical isolator using a CoFe alloy for the non-reciprocal magneto-optical (MO) transverse Kerr effect, we have measured the optical and magneto-optical indices of Co90Fe10 and Co50Fe50 alloys grown in the Al2O3/Al/CoFe/GaAs multilayer structure. The optical reflectivity and MO rotation and ellipticity measurements were performed at variable incidence angle and s and p polarization of the incident light. In order to determine the optical and MO indices, the experimental data were fitted using a Matlab implementation of a standard multilayer Yeh formalism including multiple reflections. This original procedure allows precise determination of the optical and MO indices of CoFe alloys. 相似文献
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We investigate the magneto-optical (MO) properties of multilayers containing several magnetic defects. Our numerical simulations show that each MO defect mode can be tuned independently by adjusting the structural parameters of magnetic materials. In addition, giant Faraday rotation can be obtained. Our results indicate that the structure may have potential applications for independently tunable multichannel MO isolators. 相似文献
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《Journal of magnetism and magnetic materials》2001,225(3):394-402
We describe a new scheme of noncollinear interaction geometry for magneto-optical (MO) Bragg cells based on inelastic scattering of guided optical wave beams by magnetostatic waves in yttrium–iron–garnet (YIG) films. A great increase of the diffracted light intensity was obtained when using an inclined magnetization of the film, in the case when static in-plane magnetization component is directed along the light propagation direction. It is shown that the diffraction efficiency can be increased more than two times, at a specific value of the angle (≈35°) between the saturation magnetization vector and the normal to the film surface. The effect can be explained through a four-wave model of the diffraction process, which can take place in optical waveguides with MO gyrotropy. The results obtained by a simple analytical solution of the diffraction problem are found to be in good qualitative agreement with the experimental observations. 相似文献
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Y. Tsuchiya Y. NakajimaT. Tamegai 《Physica C: Superconductivity and its Applications》2010,470(20):1123-1125
We have observed single vortices in a NbTiN thin film by using magneto-optical (MO) imaging method, in which the light reflected from the surface of the sample produces MO contrasts. The gap between the sample and the indicator film is estimated by the Newton ring and curve fitting to the flux density profile of single vortices. 相似文献
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Y.P. Lee K.W. Kim Y.V. Kudryavtsev V.V. Nemoshkalenko B. Szymański 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,26(1):41-50
Comparative study of the solid-state reaction (SSR) in a series of Ti/Ni multilayered films (MLF) with a bilayer period of
0.65-22.2 nm and a constant Ti to Ni sublayer thickness ratio has been performed by using the experimental and computer-simulated
magneto-optical (MO) and optical spectroscopies as well as X-ray diffraction (XRD). It was shown that alloyed-like regions
in an amorphous structure is spontaneously formed near the interfaces between pure elements during the film deposition. The
thickness of this region was estimated as 2-3.8 nm on the basis of the MO and optical studies. The SSR in the Ti/Ni MLF caused
by an annealing at 580 K for 60 min increases the thickness of these interfacial amorphous regions. It was shown that SSR
takes place mainly in the Ti/Ni MLF with relatively “thick” sublayers. The existence of a threshold nominal Ni-sublayer thickness
for observing the equatorial Kerr effect of about 3.0 and 4.5 nm for the as-deposited and annealed Ti/Ni MLF, respectively,
is explained by formation of the nonmagnetic alloyed regions between pure components during the film deposition as a result
of the SSR. For the case of Ti/Ni MLF, the MO and optical approaches turn out to be more sensitive in determining the thickness
of the reacted zone, while XRD is more useful for the structural analysis. It was also shown that the very thin nonreacted
Ni sublayers have different MO properties (and hence electronic structure) from the bulk.
Received 2 May 2001 and Received in final form 21 November 2001 相似文献
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We demonstrate the integration of a single-crystal magneto-optical film onto thin silicon-on-insulator (SOI) waveguides by use of direct wafer bonding. Simulations show that the high confinement and asymmetric structure of SOI allows an enhancement of approximately 3x over the nonreciprocal phase shift achieved in previous designs; this value is confirmed by our measurements. Our structure will allow compact magneto-optical nonreciprocal devices, such as isolators, integrated on a silicon waveguiding platform. 相似文献
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J. Bai S. F. Fu S. Zhou X. Z. Wang 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,83(3):343-348
We investigate one magnetically nonlinear response of antiferromagnetic (AF) films to
incident electromagnetic waves, or the reflective optical bi-stability (ROB). Such
geometry is used, where the AF anisotropy axis and external static magnetic field both are
parallel to the film surfaces and normal to the incident plane. For TE incident waves with
the electric component transverse to the incident plane, the ROB of the AF film with the
absorption is calculated, but the case of TM incident waves is neglected since no magnetic
nonlinearity is induced in this geometry. The bi-stability is completely different in the
two resonant-frequency vicinities. Two kinds of bi-stability are found in the higher
vicinity, and their features versus incident power are opposite. We also find that there
are critical incident angle and critical film thickness for the existence of bi-stability.
The bi-stability disappears when the film thickness or incident angle exceeds its critical
value. Because the properties of bi-stable reflection sensitively depend on the external
field and the incident angle, this bi-stability can be easily modulated by means of
changing these quantities. 相似文献