Spatial light modulators(SLM),capable of dynamically and spatially manipulating electromagnetic waves,have reshaped modern life in projection display and remote sensing.The progress of SLM will expedite next-generation communication and biomedical imaging in the terahertz(THz)range.However,most current THz SLMs are adapted from optical alternatives that still need improvement in terms of uniformity,speed,and bandwidth.Here,we designed,fabricated,and characterized an 8×8THz SLM based on tunable liquid crystal metamaterial absorbers for THz single-pixel compressive imaging.We demonstrated dual-color compressive sensing(CS)imaging for dispersive objects utilizing the large frequency shift controlled by an external electric field.We developed auto-calibrated compressive sensing(ACS)algorithm to mitigate the impact of the spatially nonuniform THz incident beam and pixel modulation,which significantly improves the fidelity of reconstructed images.Furthermore,the complementary modulation at two absorption frequencies enables Hadamard masks with negative element values to be realized by frequency-switching,thereby halving the imaging time.The demonstrated imaging system paves a new route for THz single-pixel multispectral imaging with high reliability and low cost.

Weili Li;Xuemei Hu;Jingbo Wu;Kebin Fan;Benwen Chen;Caihong Zhang;Wei Hu;Xun Cao;Biaobing Jin;Yanqing Lu;Jian Chen;Peiheng Wu

Research Institute of Superconductor Electronics(RISE),School of Electronic Science and Engineering,Nanjing University,Nanjing 210023,China;School of Electronic Science and Engineering,Nanjing University,Nanjing 210023,China;Purple Mountain Laboratories,Nanjing 211111,China;National Laboratory of Solid State Microstructures,Collaborative Innovation Center of Advanced Microstructures and College of Engineering and Applied Sciences,Nanjing University,163 Xianlin Avenue,Nanjing 210023,China

光：科学与应用（英文版）

[1]Weili Li;Xuemei Hu;Jingbo Wu;Kebin Fan;Benwen Chen;Caihong Zhang;Wei Hu;Xun Cao;Biaobing Jin;Yanqing Lu;Jian Chen;Peiheng Wu-.Dual-color terahertz spatial light modulator for single-pixel imaging)[J].光：科学与应用（英文版）,2022(07):1585-1594

8THz,halving

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