Programmable metasurfaces allow dynamic and real‐time control of electromagnetic (EM) waves in subwavelength resolution, holding extraordinary potentials to establish meta‐systems. Achieving independent and real‐time controls of orthogonally‐polarized EM waves via the programmable metasurface is attractive for many applications, but remains considerably challenging. Here, a polarization‐controlled dual‐programmable metasurface (PDPM) with modular control circuits is proposed, which enables a dibit encoding capability in modifying the phase profiles of x‐ and y‐polarized waves individually. The constructed extended interface circuit is able to extend the number of control interfaces from a field programmable gate array by orders of magnitude and also possesses memory function, which enhance hugely the rewritability, scalability, reliability, and stability of PDPM. As a proof‐of‐concept, a wave‐based exclusive‐OR logic gate platform for spin control of circularly‐polarized waves, a fixed‐frequency wide‐angle dual‐beam scanning system, and a dual‐polarized shared‐aperture antenna are demonstrated using a single PDPM. The proposed PDPM opens up avenues for realizing more advanced and integrated multifunctional devices and systems that have two independent polarization‐controlled signal channels, which may find many applications in future‐oriented intelligent communication, imaging, and computing technologies.

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Signal conversion plays an important role in many applications such as communication, sensing, and imaging. Realizing signal conversion between optical and microwave frequencies is a crucial step to construct hybrid communication systems that combine both optical and microwave wireless technologies to achieve better features, which are highly desirable in the future wireless communications. However, such a signal conversion process typically requires a complicated relay to perform multiple operations, which will consume additional hardware/time/energy resources. Here, we report a light-to-microwave transmitter based on the time-varying and programmable metasurface integrated with a high-speed photoelectric detection circuit into a hybrid. Such a transmitter can convert a light intensity signal to two microwave binary frequency shift keying signals by using the dispersion characteristics of the metasurface to implement the frequency division multiplexing. To illustrate the metasurface-based transmitter, a hybrid wireless communication system that allows dual-channel data transmissions in a light-to-microwave link is demonstrated, and the experimental results show that two different videos can be transmitted and received simultaneously and independently. Our metasurface-enabled signal conversion solution may enrich the functionalities of metasurfaces, and could also stimulate new information-oriented applications.

Invisibility cloaks, a class of attractive devices that can hide objects from external observers, have become practical reality owing to the advent of metamaterials. In previous cloaking schemes, almost all demonstrated cloaks are time‐invariant and are investigated in the system that is motionless, and hence they are limited to hide stationary objects. In addition, the current cloaks are typically static or require manual operation to achieve dynamic cloaking. Here, a smart Doppler cloak operating in broadband and full polarizations is reported, which consists of a time‐modulated reflective metasurface and a sensing‐feedback time‐varying electronic control system. Experimental results show that the smart Doppler cloak is able to respond self‐adaptively and rapidly to the ever‐changing velocity of moving objects and then cancel different Doppler shifts in real time, without any human intervention. Moreover, the wideband and polarization‐insensitive features enable the cloak to be more robust and practical. To illustrate the capabilities of the proposed approach, the smart Doppler cloak is measured in three scenarios with two different groups of linearly‐polarized incidences at 3.3 and 4.9 GHz, and one group circularly‐polarized incidences at 6.0 GHz, respectively.

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