Programmable all-thermal encoding with metamaterials

Advanced encoding technologies are crucial for information processing and storage, and have been widely studied and implemented in various wave fields such as electromagnetics and acoustics. However, heat has not been commonly utilized as a significant carrier of information due to the lack of programmability with flexible unit structures, which severely limits its practical applications. In this context, we first propose a novel programmable all-thermal encoding strategy that utilizes macroscopic conductive heat for digital encoding under purely thermal fields. Our approach leverages switchable cloak-concentrator metadevices to distinguish and modulate binary signals based on the divergent features of heat flows on each unit. The encoding operation is made programmable with the use of temperature-responsive phase change materials, which benefit from the self-adaptive external-stimulus and internal-response mechanism. To demonstrate the feasibility of our approach, we fabricate a proof-of-concept prototype using shape memory alloys that exhibit phase-change behavior under specific temperatures, resulting in a robust thermal encoding platform. This proposed scheme presents a practical paradigm for all-thermal logical metadevices and opens up new avenues for implementing modern information technologies in ubiquitous diffusion systems.