Reconfigurable metasurface with liquid crystal alignment effect for next-generation meta-LCoS devices

Abstract

Active metasurface is attracting a growing amount of attention from industry. Although several potential routes to achieve active metasurface have been proposed, liquid crystal (LC)-based approach, which relies on metasurface immersed in LC environment, is among the most promising methods due to the well-established assembly and packaging processes for LC devices. At the same time, some long-lasting issues of LC devices can be addressed with the introduction of metasurface, such as the slow response speed and limited resolution. In this work, we demonstrate an LC-based active metasurface (LCAM) device with electrically tunable reflection at near-infrared wavelength. The response time was determined to be sub-milliseconds, thanks to the 1-μm cell gap. More importantly, we found that the metasurface also provides alignment for the LC, which potentially could replace the alignment process in conventional LC devices. Our work presents a feasible option to improve the performance of LC-based devices such as liquid crystal on silicon (LCoS).