高同質性的磁性流體薄膜在受到外加垂直磁場作用下，磁性粒子沿著外加磁場聚集形成磁性圓柱體。這些磁性圓柱體在薄膜中排列成二維的六角形晶格陣列，因此具有光柵的作用。而磁性圓柱體的間柱是在微米的範圍內，此範圍恰好能對可見光產生繞射作用。我們的結果發現當白光光源垂直入射磁流體薄膜，可得到一彩色的繞射圓環。我們稱其為磁色效應(Magnetochromatic effects)。對單一波長的入射光而言，其繞射光的強度在空間中的分布與光柵公式完全符合。
由於磁性圓柱體的間距是可用許多參數來調制的，諸如外加磁場的強度、磁場增率、薄膜厚度…等。所以隨著不同參數的調制，使得磁性圓柱體的間距隨之改變，白光光源入射薄膜產生繞射圖樣亦有變化。上列參數對磁色效應的影響，在本研究作逐一的探討。

When a magnetic field H was applied perpendicularly to the magnetic fluid thin film, the magnetic particles agglomerated to form particle columns. As the H was further increased, the crystallized two-dimensional hexagonal lattices of magnetic particle columns were constructed. Theses ordered hexagonal lattices could act as a 2D optical grating. Further, the distance between magnetic particle columns is in the range of micrometers and capable to generate diffraction pattern for visible light. Hence, a parallel white light ray normally passing through the thin film under the external field, the colorful diffraction pattern was observed. This phenomenon can be called the “magnetochromatic effects”. For specific wavelength incident light, the spatial distribution of the diffracted intensity was consistent with the grating equation.
Due to the tunable distance of the magnetic columns by many parameters, such as external magnetic field strength, ramping rate and thickness of the thin film…etc, the distance of the magnetic columns varied with different parameters. The diffraction pattern also changed when the white light ray normally passed through the thin film. In our research, we made a series of explores in the relationship of the magnetiochromatic effects with the different parameters.

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