Fast-switching reconfigurable metadevice with metasurface-induced liquid crystal alignment for light modulator applications

Abstract

Metasurface technology is progressing rapidly towards commercialization and productization, due to its unparallelled advantages over conventional optical solutions. The reconfigurable metasurface, exhibiting more flexibility and capacity than its static counterpart, has been one of the most pursued features of metasurface. In this work, we present liquid crystal-based dynamic metasurface by immersing metasurface in nematic liquid crystal environment. No alignment material was used, and liquid crystal was aligned directly by metasurface. The alignment quality was characterized and the intensity contrast of 33 was obtained. Optical amplitude modulation was achieved with the modulation depth of 91% at the wavelength of 1375 nm. Moreover, sub-micrometre cell gap of 875 nm was realized, and the response time was measured to be sub-millisecond at room temperature, translating to > 1KHz operation frequency. The higher operation frequency of > 3.4 KHz was recorded at elevated temperature. The key performance indicators demonstrated in this work showcase the promising future of liquid crystal – based reconfigurable metasurface, especially for fast light modulator applications.//Metasurface technology is progressing rapidly toward commercialization and productization due to its unparalleled advantages over conventional optical solutions. The reconfigurable metasurface, exhibiting more flexibility and capacity than its static counterpart, has been one of the most pursued features of the metasurface. In this work, we present a liquid crystal-based dynamic metasurface by immersing the metasurface in a nematic liquid crystal environment. No alignment material was used, and liquid crystal was aligned directly by metasurface. The alignment quality was characterized, and the intensity contrast of 33 was obtained. Optical amplitude modulation was achieved with a modulation depth of 91% at the wavelength of 1375 nm. Moreover, a sub-micrometer cell gap of 875 nm was realized, and the response time was measured to be sub-millisecond at room temperature, translating to > 1KHz operation frequency. The higher operation frequency of > 3.4 KHz was recorded at elevated temperatures. The key performance indicators demonstrated in this work showcase the promising future of liquid crystal-based reconfigurable metasurface, especially for fast light modulator applications.