Recently, Dr. Muhammad Shemyal Nisar, one of SBC engineering lecturers, published an article titled “Polarization insensitive non-interleaved frequency multiplexed dual-band Terahertz coding metasurface for independent control of reflected waves” in Scientific Reports (3.8, JCR-Q2). This study was worked together with experts and lectures from State Key Laboratory of Radio Frequency Heterogenous Integration, Guangdong Engineering Research Centre of Base Station Antennas, Shenzhen Key Laboratory of Antennas and Propagation, College of Electronics and Information Engineering and College of Physics and Optoelectronics engineering of Shenzhen University.
Independent control of electromagnetic (EM) waves by metasurfaces for multiple tasks are highly desired and is the recent hot topic of research. In this work we contribute a polarization insensitive frequency multiplexed 2-bit coding metasurface to control the Terahertz (THz) waves in the two operating bands independently. In this regard, as a first step a cascaded meta-atom composed of square rings and/or square metallic patches separated by two polyimide substrates is designed and optimized that provides sixteen independent distinct discrete phases in the reflection geometry. These meta-atoms are then distributed with distinct coding sequences in the two-dimensional spatial plane to realize various bi-functional metasurfaces.
As a proof of the concept various full structures are designed and simulated to realize a series of bi-functionalities including anomalous reflection/beam shaping, beam shaping/anomalous reflection, beam deflection/Orbital angular momentum (OAM) beam generation with distinct modes and propagating wave to surface wave (PW–SW) conversion/PW beam manipulation in the lower and higher THz bands, respectively. All the simulation results are in excellent agreement with their theoretical equivalents. We envision that the proposed meta-designs have potential applications for the multi-spectral control of EM waves in THz band. The proposed idea has the potential to design polarization-insensitive multi-spectral multipurpose meta-devices in the THz regime, which could find application in multi-color holography and frequency beam manipulators for the spatial separation of signals modulated with different frequencies.
Related: https://www.nature.com/articles/s41598-024-71910-5
