Programmable Terahertz Grafted Vortex Interference Based on Patterned Transparent Electrodes and Liquid Crystal Anisotropy‐Induced Chiral Field
Huijun Zhao, Jiaxing Guo, Yiming Wang, Chengwei Song, Jing Liu, Hao Wang, Yunyun Ji, Shiqiang Zhao, Jierong Cheng, Fei Fan, Shengjiang Chang
Abstract
Abstract The generation of vortex beams with multiple orbital angular momentum (OAM) modes by a single photonic device is of great attraction, which has important applications in information coding, anti‐interference transmission, and particle manipulation, but the active manipulation of their interference field still faces challenges from functional materials and device integration. In this work, a terahertz (THz) grafted vortex interference technique is demonstrated by means of a programmable metadevice that integrates patterned graphene electrodes, a liquid crystal layer, and a helical dielectric metasurface. In this approach, a liquid crystal anisotropy‐induced chiral field is generated to overcome spin‐locking restrictions between two co‐spin channels. The THz transparent electrode based on patterned graphene layers addresses the driving challenges of liquid crystal integrated non‐metallic metasurfaces and enables dynamic phase reconstruction with multi‐pixel and multilevel encoding control. Finally, the experimental results show that a total of 2 × 5 16 interference patterns can be synthesized and quasi‐continuously controlled in the 0.5–0.6 THz band with different spatial grafted OAMs via 16‐pixel encoding and different spin distribution ratios via 5‐level phase modulation. This strategy breaks through the limitations of vortex interference field states and independent spin channels, opening up new avenues for developing multifunctional photonic chips capable of executing complex optical tasks.