Classical thermodynamics often helps to passively describe macroscopic heat phenomena of natural systems, which means people almost cannot change the heat phenomena, but understand them according to the four thermodynamic laws. In contrast, thermal metamaterials, together with the governing theories, make it possible to actively manipulate macroscopic heat phenomena of artificial systems, which enables people to change the heat phenomena at will. Such metamaterials or metamaterial-based devices refer to those artificial structures that yield novel functions in controlling heat transfer. Since the concept of thermal cloak was proposed in 2008, this field has been developed rapidly with fruitful research results, which range from both theoretical models and experimental techniques in scientific research to practical applications in industry, such as radiative cooling and infrared camouflage. In this review, we comb through the research history of thermal metamaterials, and present novel functions and their associated theories in four areas. Such theories include both transformation theories and their extended theories, which are called theoretical thermotics for convenience. The four areas are classified according to the different ways of heat transfer, namely, heat conduction, heat conduction–convection,​ heat conduction–radiation, and heat conduction–convection–radiation. The corresponding experiments and applications are also introduced. At last, we provide our views on future opportunities and challenges in thermotics of metamaterials.

经典的热力学通常有助于被动地描述自然系统的宏观热现象，这意味着人们几乎无法改变热现象，而是根据四个热力学定律来理解它们。相比之下，热超材料与主导理论一起使主动地操纵人造系统的宏观热现象成为可能，这使人们能够随意改变热现象。这样的超材料或基于超材料的装置是指在控制传热方面产生新颖功能的那些人造结构。自从2008年提出隐身斗篷的概念以来，该领域得到了迅速发展，并取得了丰硕的研究成果，涵盖了从科学研究的理论模型和实验技术到工业上的实际应用，例如辐射冷却和红外伪装。在这篇综述中，我们梳理了热超材料的研究历史，并在四个方面介绍了新颖的功能及其相关的理论。这样的理论既包括变换理论，又包括扩展理论，为方便起见被称为理论热力学。根据传热的不同方式对这四个区域进行了分类，即传热，传热-对流，传热-辐射和传热-对流-辐射。还介绍了相应的实验和应用。最后，我们对超材料热力学的未来机遇和挑战提出了自己的看法。并从四个方面介绍了新颖的功能及其相关的理论。这样的理论既包括变换理论，又包括扩展理论，为方便起见被称为理论热力学。根据传热的不同方式对这四个区域进行了分类，即传热，传热-对流，传热-辐射和传热-对流-辐射。还介绍了相应的实验和应用。最后，我们对超材料热力学的未来机遇和挑战提出了自己的看法。并从四个方面介绍了新颖的功能及其相关的理论。这样的理论既包括变换理论，又包括扩展理论，为方便起见被称为理论热力学。根据传热的不同方式对这四个区域进行了分类，即传热，传热-对流，传热-辐射和传热-对流-辐射。还介绍了相应的实验和应用。最后，我们对超材料热力学的未来机遇和挑战提出了自己的看法。热传导，热传导-对流，热传导-辐射和热传导-对流-辐射。还介绍了相应的实验和应用。最后，我们对超材料热力学的未来机遇和挑战提出了自己的看法。热传导，热传导-对流，热传导-辐射和热传导-对流-辐射。还介绍了相应的实验和应用。最后，我们对超材料热力学的未来机遇和挑战提出了自己的看法。