纵向磁场下铁磁流体磁致旋光效应的互易性  

Reciprocity Property of Magneto-optical Rotation Effect of Ferrofluid Exposed to the Longitudinal Magnetic Field

作　　者：王士彬[1,2] 杜林[1] 孙才新[1] 林森[1] 杨勇[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030 [2]重庆理工大学电子信息与自动化学院,重庆400050

出　　处：《高电压技术》2010年第8期2028-2034,共7页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2009CB724504);重庆市自然科学重点基金项目(2007BA2002);输配电装备及系统安全与新技术国家重点实验室自主项目(2007DA10512708302)~~

摘　　要：为应用铁磁流体磁致旋光特性于光电式电流/磁场测量领域进行了相关特性的研究。通过测量在纵向磁场作用下的透射光强,发现铁磁流体与磁光玻璃不同即磁场方向逆转并不会引起铁磁流体对于偏振光旋转方向的变化。利用此特性设计了一种双反光路的电流/磁场测量系统,可以提高测量系统的抗干扰能力并降低光源功率波动带来的测量误差。电磁理论分析表明,铁磁流体旋光效应具有互易性的本质原因在于介电张量的非对角项具有反对称性,nm磁性颗粒在外加磁场作用下其磁化矢量具有较小的弛豫时间,能够在极短时间内跟随外加磁场的逆转而发生定向磁化。该研究结果与"人工磁光材料均具有非互易性"的传统认识不同,有助于对铁磁流体磁致旋光效应的理解和应用。It is the precondition for ferrofluid to study of property of magneto-optical rotation effect when applying it to the measurement of photo-electrical electric current or magnetic field. By measuring the intensity of transmitted light, the experimental results show that different from the magneto-optical glass, the rotation direction does not change for the reversal direction of magnetic field. A measurement system with a double reflection light path is designed to reduce the measurement error due to the power fluctuation of light source and to improve the anti-interference ability. The dissymmetry of non-diagonal item of the dielectric tensor is proved by the electromagnetic theory. The magnetic nanoparticles in ferrofluid with small relaxation time when it is exposed to the alternating magnetic field. The orientation magnetization occurred following with the reversal direction magnetic field in a short time. The opinions disapprove of the traditional viewpoints about artificial magneto-optical materials, and it is beneficial to understanding and applying the magneto-optical effects of ferrofluid.

关 键 词：铁磁流体 磁致旋光效应 互易性 介电张量 磁光玻璃 双反光路 

分 类 号：O482[理学—固体物理]