Programmable All-Thermal Encoding with Metamaterials

Information processing and storage depend on advanced encoding technologies, which have been studied and implemented adequately in wave fields ranging from electromagnetics to acoustics. However, heat is seldom utilized in signal transfer as a significant carrier of information. One critical reason is the lack of programmability with flexible unit structures, drastically limiting its practical applications. Here, we first propose and realize a programmable all-thermal encoding strategy, where macroscopic conductive heat is used for digital encoding under purely thermal fields. Thanks to the switchable cloak-concentrator metadevices, binary signals are distinguishable and modulated by the divergent features of heat flows on each unit. Temperature-responsive phase change materials benefit the iterative encoding operation (programmability) according to the self-adaptive external-stimulus and internal-response mechanism. A proof-of-concept prototype is fabricated with the help of shape memory alloys due to their phase-change behavior under specific temperatures, yielding a robust thermal encoding platform. The proposed scheme sets up a practical paradigm for all-thermal logical metadevices, and paves a different avenue for implementing modern information technologies in ubiquitous diffusion systems.