Plasmonic metasurfaces represent a new class of quasi two-dimensional metamaterials that provide fascinating capabilities for manipulating light with an ultrathin platform. Such metasurfaces allow for generating a wide range of position-dependent discontinuous interfacial phase profiles. By simply engineering the metasurface-induced phase profile, a nearly arbitrary wavefront can be achieved. This unique approach promises interesting device applications beyond the scope of conventional components that rely on gradual phase accumulation for wavefront shaping. Several exotic phenomena have been demonstrated using metasurfaces including anomalous reflection and refraction,[1] the spin Hall effect of light, plasmonic metalens, optical polarization conversion, among others. Recently, metasurfaces have been also used to achieve computer-generated holograms (CGH) with high efficiency and high image quality in the visible and near-infrared regions.[2] The dispersionless nature of metasurfaces enables broadband operation without sacrificing the image quality. Thus, metasurface holograms feature a great advantage over other conventional methods such as CGH with spatial light modulators or diffraction optical elements.
In this work, we demonstrate dynamic plasmonic holography based on catalytic magnesium (Mg) metasurfaces in the visible range. Through the unique hydrogenation and dehydrogenation between Mg and magnesium hydride (MgH2), different information components on the plasmonic holograms become fully addressable in space and can be individually switched on/off. These results in dynamic plasmonic holograms with designated multiple states, giving rise to high-level information control with unprecedented dynamic performance. Our work outlines the inevitable transformation from metasurfaces to metadevices, opening the door to a futuristic research horizon. Such dynamic plasmonic holograms will allow for a wealth of applications for high-resolution displays,[3] advanced security labels, high-density data storage and information processing.
References
[1] Yu, N. et al. Light Propagation with phase discontinuities: generalized laws of reflection and refraction. Science 334, 333–337 (2011).
[2] Zheng, G. et al. Metasurface holograms reaching 80% efficiency. Nat. Nano. 10, 308–312 (2015).
[3] Duan, X. et al. Dynamic plasmonic colour display. Nat. Commun. 8, 14606 (2017).
Photonic & plasmonic nanomaterials , Optical properties of nanostructures , Metamaterials
