A high-performance thermal transistor based on interfacial negative differential thermal resistance

A thermal transistor, which can achieve the smart, flexible, and precisely controlled thermal management, proves to be a promising thermal device. Recently, thermal transistors based on the negative differential thermal resistance (NDTR) have been regarded as the most feasible configuration considering their simple structures. Among the several methods to implement NDTR, the method of reducing the contact pressure between mated surfaces by using the negative thermal expansion material, thus generating a negative temperature dependent interface thermal conductance and accompanied NDTR, is the most likely to be observed experimentally. In this paper, a thermal transistor based on NDTR is designed by engineering the interfacial thermal resistance. Moreover, we optimize the switching function and the amplification function of the transistor by only adjusting the temperature and the length of the source terminal. As an example, a silicon thermal transistor with a high switching ratio as well as an accurately controlled thermal flux amplification function is discussed at low temperature. The design and optimization of macroscopic thermal transistor will promote the rapid development of thermal functional devices and help to control thermal flux in a more flexible and effective way.