利用波矢滤波超表面实现超衍射成像

Super diffraction imaging with wave vector selective metasurface

超衍射成像是当前光学领域的研究热点.本文利用一种不对称分裂环超表面结构来实现超衍射成像,该结构由上下两个不对称的金属环组成,通过集体陷模共振可实现对入射光的波矢选择性透过.当物体发出或反射的光照射到超表面上时,入射角大于某一角度的入射光会被共振电场耦合吸收或反射,只有低空间频率的光波可以通过,从而减小衍射的影响,实现超衍射成像.数值模拟结果表明了这一方法的可行性.

Super diffraction imaging has been a research hotspot for a long time.We realize the super diffraction imaging with a metasurface structure,which is consisted of asymmetrically split rings.Based on the wave vector selectivity of the metasurface,radiation can be transmitted through it only in a narrow range of the incident angular.The metasurface acts as a high frequency spatial filter,reduces the diffraction effect,and obtains the super diffraction resolution.Numerical simulation results demonstrate the validity of this method.