摘要
提出了一种在矩形金属沟槽中插入两块相同的矩形硅核的新型杂化波导结构,基于有限元方法,在波长为1550 nm时,系统地研究了两块介质核间的距离、介质核的高度、宽度以及介质核与金属间的距离对有效模面积和传播距离的影响。计算结果表明,通过左右狭缝或者中间狭缝的场增强效应,能得到低损耗超小模面积的杂化模,当介质核与金属间的距离比较大时,相对于中间无狭缝的情况,当缝隙为5 nm时,该结构的有效模面积急剧减小,约减到原来的七分之一,而传播距离略有增长,在50个波长左右,而且中间缝隙越窄(不等于0 nm),模面积越小,传播距离越大,介质核越高,传播距离越远而模面积几乎不变。当介质核与金属间的距离比较小时,中间缝隙越小,介质核的宽度越小,模面积越小。
A novel hybrid waveguide structure of rectangular silicon insert two identical nuclei in a rectangular metal trench is presented. Based on the finite element method, variations of effective mode area and propagation distance with distance between the two nuclear medium, nuclear medium height and width, the distances between dielectric core and metal are systematic studied at a wavelength of 1550 nm. Calculated results show that the enhanced effect of field in gaps of the dielectric core or between dielectric core and metal can get a low loss hybrid mode of ultra-small modal area. When the distances between dielectric core and metal is wide, the gap in dielectric core is 5 nm, effective mode area of the structure is drastically reduced to about one-seventh respect to the nuclear medium with no gap and the propagation distance increasing a slight remains at 50 wavelengths around. And the smaller the mode area is, the longer the propagation distance is. The higher the gap dielectric core is, the smaller the propagation distance is, and the mode area is almost invariably. When the height of dielectric core is higher, the propagation distance is longer, but the effective mode area changes minor. When the distance between dielectric core and metal is narrow, the gap of nuclear medium and nuclear medium width are much narrower, the effective mode area are smaller.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2015年第6期284-293,共10页
Acta Optica Sinica
基金
国家自然科学基金(11464014
11347215)
湖南省自然科学基金(13JJ6059
13JJB015
13JJB010)
湖南省教育厅科学研究项目(13C750
13B091)
关键词
光学器件
杂化表面等离激元波导
有限元理论
有效模面积
传播距离
optical devices
hybrid surface plasmon polariton waveguide
finite element theory
effective modal area
propagation length
