摘要
当入射角大于全反射临界角时,双棱镜结构中透射和反射光束的古斯汉欣(Goos-Hanchen)位移具有饱和效应,并且只有波长数量级。利用稳态相位法研究了当入射角小于全反射临界角时双棱镜结构中透射光束的古斯汉欣位移。研究表明,传播模式下透射光束的古斯汉欣位移是空气层厚度、入射角和双棱镜折射率的周期性函数。当透射共振时,透射光束的古斯汉欣位移可达入射波长的几十倍,与入射角大于全反射临界角的情况相比,透射光束的位移通过边界的相互作用具有共振增强效应;在非共振点处,对称结构中的反射光束具有与透射光束相同的古斯汉欣位移。共振增强的透射光束的位移在光开关及光耦合器中具有潜在的应用。
Goos-Hnchen (GH) shifts of the transmitted and reflected light beam in a two-prism configuration is staturated to a maximum in the opaque limit for the incidence angle above the critical angle for total reflection. The magnitude of GH shift is about the order of the wavelength. The Goos-Hnchen shift of the transmitted light beam in a two-prism configuration is investigated by stationary-phase approach when the incidence angle is less than the critical angle. It is shown that the Goos-Hnchen shift of the transmitted light beam in propagating case is a periodical function of the air-gap thickness, incidence angle and the refractive index of two prisms. Due to transmission resonance, the Goos-Hnchen shift of the transmitted light beam can be of one or two order of wavelength. Compared to the result for the incidence angle above the critical angle, the Goos-Hnchen shift presented here can be resonantly enhanced by boundary interaction effect. It is also shown that the Goos-Hnchen shift of the reflected light beam is the same as that of the transmitted one in the symmetric structure, when the resonance does not occur. These resonance-enhanced shifts of the transmitted light beam may lead to potential applications in the optical devices, such as optical switch and optical coupler.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2005年第5期673-677,共5页
Acta Optica Sinica
基金
国家自然科学基金(60377025)
上海市教委曙光计划(01SG46)
上海市教委基金(04AC99)
上海市青年科技启明星跟踪计划(03QMH1405)
上海市科委基础研究重点项目(04JC14036)
上海市教委重点学科资助课题。
关键词
物理光学
有限波束
共振增强
稳态相位法
physical optics
finite-sized light beam
resonance enhancement
stationary-phase approach
