基于耦合介质纳米线的深亚波长局域波导  

Dielectric waveguide with deep subwavelength mode confinement based on coupled nanowires

作　　者：岳嵩[1] 李智[1] 陈建军[1] 龚旗煌[1] 

机构地区：[1]北京大学物理系,人工微结构和介观物理国家重点实验室,北京100871

出　　处：《物理学报》2011年第9期404-410,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10804004,10821062,90921008);国家重点基础研究发展计划(973计划)(批准号:2007CB307001,2009CB930504)资助的课题~~

摘　　要：提出了一种基于耦合介质纳米线的深亚波长局域波导,通过两根紧邻的高折射率介质纳米线的耦合,该波导可以将光场有效束缚在纳米线之间的低折射率纳米缝隙中.计算模拟的结果表明,该波导的有效模场面积达到λ02/200,比单根纳米线波导小一个数量级,这种深亚波长的模场束缚能力可以与表面等离激元混合波导相比拟.计算模拟的结果还表明,纳米线可能带有的低折射率氧化膜、低折射率衬底的存在、以及纳米线间尺寸存在的一定差异对于该波导结构的实际应用都不会产生很大的影响.由于介质波导理论上的传输长度为无穷大,因此这种深亚波长局域的耦合介质纳米线波导有可能在未来的集成光子学回路中获得广泛应用.Dielectric waveguide with deep subwavelength mode confinement based on coupled semiconductor nanowires is proposed.Through the coupling between two adjacent nanowires with high refractive indexes, light can be efficiently confined in the nano-gap between the nanowires with a low refractive index. Numerical simulations indicate that the effective mode area of such a waveguide can be as small as λ20/200, which is one order of magnitude smaller than that of a single nanowire, and such a mode confinement is comparable to that of hybrid plasmonic waveguide. It is also shown that from the view of real applications, possible existing low refractive index oxidization layers of nanowires, low refractive index substrate and small deviation of nanowire dimensions do not have significant influence on the property of the waveguide. As the propagation length is theoretically infinite for dielectric waveguides, such a coupled nanowire waveguide with deep subwavelength mode confinement may have important applications in future integrated photonic circuits.

关 键 词：介质波导 亚波长局域 表面等离激元波导 纳米线 

分 类 号：TN252[电子电信—物理电子学]