Department of Applied Physics, The Benin School of Engineering and Computer Science, The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem , Jerusalem, 91904, Israel.
Nano Lett. 2017 Feb 8;17(2):1127-1131. doi: 10.1021/acs.nanolett.6b04740. Epub 2017 Jan 30.
In recent years, dielectric and metallic nanoscale metasurfaces are attracting growing attention and are being used for variety of applications. Resulting from the ability to introduce abrupt changes in optical properties at nanoscale dimensions, metasurfaces enable unprecedented control over light's different degrees of freedom, in an essentially two-dimensional configuration. Yet, the dynamic control over metasurface properties still remains one of the ultimate goals of this field. Here, we demonstrate the optical resonant interaction between a form birefringent dielectric metasurface made of silicon and alkali atomic vapor to control and effectively tune the optical transmission pattern initially generated by the nanoscale dielectric metasurface. By doing so, we present a controllable metasurface system, the output of which may be altered by applying magnetic fields, changing input polarization, or shifting the optical frequency. Furthermore, we also demonstrate the nonlinear behavior of our system taking advantage of the saturation effect of atomic transition. The demonstrated approach paves the way for using metasurfaces in applications where dynamic tunability of the metasurface is in need, for example, for scanning systems, tunable focusing, real time displays, and more.
近年来，介电常数和金属纳米级超表面受到越来越多的关注，并被应用于各种领域。超表面能够在纳米尺度上引入光学性质的突然变化，从而能够对光的不同自由度进行前所未有的控制，其结构基本为二维形式。然而，对超表面性质的动态控制仍然是该领域的最终目标之一。在这里，我们展示了由硅制成的具有形式双折射的介电常数超表面与碱金属原子蒸汽之间的光学共振相互作用，从而控制并有效地调节最初由纳米级介电常数超表面产生的光学传输模式。通过这样做，我们提出了一个可控的超表面系统，其输出可以通过施加磁场、改变输入偏振或改变光频率来改变。此外，我们还利用原子跃迁的饱和效应展示了我们系统的非线性行为。所展示的方法为在需要超表面动态可调性的应用中使用超表面铺平了道路，例如扫描系统、可调焦、实时显示等。
