摘要
光自旋霍尔效应所产生的横向IF(Imbert-Fedorov)位移一般仅为亚波长量级,因此极大地限制了该效应在精密度量领域的应用.该文提出一种金属/双折射材料/金属(MIM)的多层结构,通过直接耦合方式激发该结构中的振荡模式,并利用双折射特性形成偏振相关的小角度共振,以此来增强光自旋霍尔效应.理论分析表明:上述设想可将可见光波段的横向IF位移增强到可以直接观察的亚毫米甚至毫米量级.
Conventionally, the Imbert-Fedorov shift generated by the spin Hall effect of light is of sub-wavelength scale,which hinders its application in fields such as precision metrology. In this paper,a very simple planar metal/ insulator/metal （ MIM） structure is proposed, where the insulator layer is made of birefringent material and acts as the guiding layer to support oscillating guided modes. These modes,also known as the high order modes,can be di-rectly excited via the free space coupling technology. The key factor is that resonance may occur at very small inci-dent angle,even approaches normal incidence. On the other hand, the induced birefringence will result in mode splitting,so that the reflectivity spectrum of the waveguide structure is no longer mode independent. Combined the two factors mentioned above, the IF shift of this simple structure can be significantly enhanced, and theoretical esti-mated value can approaches sub-millimter or millimeter scale,which is possible to be observed by naked eyes.
出处
《江西师范大学学报（自然科学版）》
CAS
北大核心
2018年第1期52-56,共5页
Journal of Jiangxi Normal University(Natural Science Edition)
基金
国家自然科学基金(11404092,11574072,61505073),江苏省自然科学基金(SBK2014043338),第60批博士后基金(2016M601586)和中央高校基本科研业务费专项资金(2017B14714)资助项目.
