Magnetochromatic effects in the magnetic fluid thin film

• Main Authors: Shu-Lian Lee, 李淑蓮
• Other Authors: Herng-Er Horng
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/44540804610680395533

碩士 === 國立臺灣師範大學 === 物理研究所 === 87 === 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.