带壳颗粒复合介质光学双稳的温度效应  

Effect of temperature on optical bistability of coated granular composites

作　　者：吴亚敏[1] 陈国庆[1] 

机构地区：[1]江南大学理学院,无锡214122

出　　处：《物理学报》2009年第3期2056-2060,共5页Acta Physica Sinica

摘　　要：研究非稀释极限下带壳的球形颗粒复合介质体系光学双稳的温度效应.其中带壳颗粒是由具有线性响应的核和非线性响应的壳层组成.由于复合体系中的空间局域场是不均匀的,所以应用自洽平均场理论,解析推导核内电场平方的空间平均值与外电场的关系表达式,并对不同温度及不同结构参数下的光学双稳进行了数值计算.结果表明,双稳与温度T、结构参数k和体积分数f有关.在k和f一定时,随温度的升高,双稳效应因上阈值减小、下阈值增大而逐渐减弱,直至双稳消失;在T和f一定时,随结构参数的增大,上、下阈值都增大,而上阈值的增速较大从而导致双稳区域宽度加大.We study the intrinsic optical bistability（OB） of nondilute suspensions of coated spherical particles with a metallic core and a nonlinear dielectric shell. In this kind of system,as the spatial local field is not uniform,it cannot be obtained exactly. In this connection,we establish the self-consistent mean field approximation,and obtain the spatial average of the local field squared in the core as a function of the external applied field. Numerical results show that the optical bistability（OB） is dependent on the temperature T,the structural parameter k,and the volume fraction f. For given k and f,the width of optical bistability decreases with increasing temperature. At further increasing of T,OB is found to vanish. On the other hand,for given T and f,the bistable region gradually increases as the structural parameter k increases,accompanied with the increase in both the upper and lower threshold fields. More exactly,the increase of the bistable region mainly results from the rapid increase in the upper threshold field.

关 键 词：带壳颗粒 复合介质 光学双稳 温度效应 

分 类 号：O437[机械工程—光学工程]