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Abstract Terahertz (THz) technologies have become a focus of research in recent years due to their prominent role in envisioned future communication and sensing systems. One of the key challenges facing the field is the need for tools to enable agile engineering of THz wave fronts. Here, we describe a reconfigurable metasurface based on GaN technology with an array-of-subarrays architecture. This subwavelength-spaced array, under the control of a 1-bit digital coding sequence, can switch between an enormous range of possible configurations, providing facile access to nearly arbitrary wave front control for signals near 0.34 THz. We demonstrate wide-angle beam scanning with 1° of angular precision over 70 GHz of bandwidth, as well as the generation of multi-beam and diffuse wave fronts, with a switching speed up to 100 MHz. This device, offering the ability to rapidly reconfigure a propagating wave front for beam-forming or diffusively scattered wide-angle coverage of a scene, will open new realms of possibilities in sensing, imaging, and networking. 

The concept of chip-to-chip information propagation by spoof surface plasmon polariton (SSPP) metasurface at terahertz frequency has been introduced of late, that promises data transfer with high bandwidth, low crosstalk, and low energy consumption. As the exotic electromagnetic properties of the metasurface derive from its designed geometric pattern and periodicity, any possible variation of fabrication process parameters may affect the design pattern and consequently, the information capacity of SSPP interconnects. In this work, we have investigated the extent of performance degradation of SSPP interconnect with the statistical variation of the geometric pattern of the metasurface. We also described the technique of the design of an appropriate analog circuit so that the loss of signal integrity incurred by the process variation can be recuperated in real-time. 

The bottleneck of inter-chip communication speed, for instance that between logic and memory units is a long-standing issue in acquiring ultra-fast computing. While research from two extreme ends of technologies: electrical, and optical interconnect have their own pitfall in constructing an energy-economic route of communication with high bandwidth density, a radically different technology named spoof plasmon based communication may bring new insight towards addressing the issue. This technology smoothly interweaves the advantages of electrical interconnect and that of optical ones. In the present work, we have given a proof-of-concept demonstration of the signal transfer capacity of spoof plasmon parallel data-bus. We demonstrated that the spoof plasmon channel can accommodate two different kinds of mode: electro-SSPP mode and optoSSPP mode. Depending on the data-traffic, SSPP channel can be dynamically reconfigured for supporting either of the two modes for information transfer in order to minimize energy consumption. In addition, we also endeavored to answer the question that whether the metasurface based information transfer system can be reliable in case of patterning irregularity induced by fabrication process variations.