The thermal properties of a material with a spatiotemporal modulation, in the form of a traveling wave, in both the thermal conductivity and the specific heat capacity are studied. It is found that these materials behave as materials with an internal convectionlike term that provides them with nonreciprocal properties, in the sense that the heat flux has different properties when it propagates in the same direction or in the opposite one to the modulation of the parameters. An effective medium description is presented which accurately describes the modulated material, and numerical simulations support this description and verify the nonreciprocal properties of the material. It is found that these materials are promising candidates for the design of thermal diodes and other advanced devices for the control of the heat flow at all scales.

中文翻译：

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时空调制的不可逆热材料

研究了具有时空调制的材料（以行波形式）的热导率和比热容的热学性质。已发现这些材料的行为类似于具有内部对流术语的材料，该术语为它们提供了不可逆的特性，即当热通量沿与参数调制相同的方向或相反的方向传播时，它们具有不同的特性。提出了有效的介质描述，可准确描述调制后的材料，数值模拟支持该描述并验证材料的不可逆特性。发现这些材料是用于热敏二极管和其他先进装置的设计的有前途的候选者，这些装置用于控制各种规模的热流。