A Moiré Superlattice Induced Thermal Switch for Modulating Interfacial Heat Transfer

We have invented a heat switch induced by a moiré superlattice for regulating interfacial thermal conductance (ITC). As twist angle increases, ITC decreases significantly, while ITC shows nonmonotonic changes with temperature. Research indicates that periodic structural fluctuations of moiré patterns, combined with uneven atomic stress fields, selectively control the efficiency of heat flux transmission. Larger twist angles intensify stress concentration, enhancing heat transfer, while changes in moiré pattern size and quantity increase scattering regions. Temperature-induced atomic thermal expansion also promotes heat transfer through stronger stress, but higher temperature disrupts the moiré structure, thereby increasing scattering regions. Competition between the enhanced local heat transfer capability and increased scattering regions leads to the variation of ITC with twist angle and temperature. Furthermore, higher normal loads will amplify atomic stress and suppress thermal expansion, thereby shifting the nonmonotonic temperature threshold of ITC toward higher temperatures.