Stereo metamaterial with three dimensional meta-atoms fabricated by programmable stress induced deformation for optical modulation

We present a novel stereo metamaterial composed of three-dimensional (3D) gold split ring resonators (SRRs) in array to realize considerable optical modulation. The metamaterial is fabricated by a general 3D nanofabrication technique of focused ion beam stress induced deformation (FIB-SID). Such technique is a simple-step process, allowing programmable and accurate nanoscale origami on various metal and dielectric thin films. Theoretical and experimental results manifest that the metamaterial device with the 3D SRRs as meta-atoms has reflection minimum and abrupt phase change at 5.3 μm. In addition, to demonstrate the power of FIB-SID, other 3D meta-atoms with complex geometry such as sine shape, fold-line, and swiss-roll are also produced, proving FIB-SID an ideal tool to construct various 3D optical nanostructures and devices, including plamonic antennas, metamaterials and metasurfaces.