Our paper on “Space-time-coding digital metasurfaces” [1], in collaboration with Tie Jun Cui’s Group (Southeast University), has been published in Nature Communications.
The recently proposed digital coding metasurfaces make it possible to control electromagnetic (EM) waves in real time, and allow the implementation of many different functionalities in a programmable way. However, current configurations are only space-encoded, and do not exploit the temporal dimension. Here, we propose a general theory of space-time modulated digital coding metasurfaces to obtain simultaneous manipulations of EM waves in both space and frequency domains, i.e., to control the propagation direction and harmonic power distribution simultaneously. As proof-of-principle application examples, we consider harmonic beam steering, beam shaping, and scattering-signature control. For validation, we realize a prototype controlled by a field-programmable gate array, which implements the harmonic beam steering via an optimized space-time coding sequence. Numerical and experimental results, in good agreement, demonstrate good performance of the proposed approach, with potential applications to diverse fields such as wireless communications, cognitive radars, adaptive beamforming, holographic imaging.
@article{IJ133_NatComm_9_4334_2018, author = {Zhang, Lei and Chen, Xiao Qing and Liu, Shuo and Zhang, Qian and Zhao, Jie and Dai, Jun Yan and Bai, Guo Dong and Wan, Xiang and Cheng, Qiang and Castaldi, Giuseppe and Galdi, Vincenzo and Cui, Tie Jun}, title = {Space-time-coding digital metasurfaces}, journal = {Nature Communications}, year = {2018}, volume = {9}, number = {1}, pages = {4334}, doi = {10.1038/s41467-018-06802-0}, note = {https://static-content.springer.com/esm/art%3A10.1038%2Fs41467-018-06802-0/MediaObjects/41467_2018_6802_MOESM1_ESM.pdf}, month = oct }