Department of Electrical Engineering, University of Washington, Seattle, Washington 98195, USA.
Opt Lett. 2012 Apr 15;37(8):1295-7. doi: 10.1364/OL.37.001295.
In this Letter we investigate the subwavelength imaging of a three-dimensional plasmon superlens based on the full vector wave simulations of optical wave propagation and transmission. The optical transfer functions are computed. Comparisons are made between the results of lenses with flat and periodic/random rough surfaces. We also study the problem of practical imaging system geometry using laser as an illumination source. Results show that the lens with periodic or random roughness can reduce the field interference effects, and provide improved focus on the transmission field and the Poynting flux. We illustrate that the subwavelength roughness in a plasmon lens can enhance the image resolution over a flat lens for both matched and unmatched permittivity conditions. The enhancement of resolution occurs because the introduced subwavelength roughness can amplify the evanescent wave components and suppress the surface plasmon resonance peaks.
在这封信件中，我们通过对光传播和传输的全矢量波模拟来研究基于三维等离子体超透镜的亚波长成像。我们计算了光学传递函数。对具有平面和周期性/随机粗糙表面的透镜的结果进行了比较。我们还研究了使用激光作为照明源的实际成像系统几何问题。结果表明，周期性或随机粗糙度的透镜可以减少场干扰效应，并在传输场和坡印廷通量上提供更好的聚焦。我们说明了等离子体透镜中的亚波长粗糙度可以增强在匹配和不匹配介电常数条件下相对于平面透镜的图像分辨率。分辨率的提高是因为引入的亚波长粗糙度可以放大消逝波分量并抑制表面等离子体共振峰。
