基于功能基元序构的高性能热电磁薄膜创制和制冷性能提升新机制

本研究将以开发面向高集成度、大功率核心电子元件和芯片精确控温应用的高性能热电磁制冷薄膜为目标，对基于功能基元序构的热电磁薄膜进行研究，探索大幅提高薄膜制冷性能的新方法和新机制，主要研究内容包括：在对热电功能基元和磁性功能基元的成分和结构合理设计和优化的基础上，构建热电磁多功能基元，通过制备工艺优化实现对材料的界面良好的控制；综合考虑形状、大小、对称性、居里温度分布等因素，探索最佳序构方式和合理的制备工艺手段；研究序构体系中的热电磁特性和表征方式，探索热电、自旋热以及磁电等效应的影响以及相互间的耦合作用，阐明热电磁制冷的机制。涉及的科学问题包括：热电磁多功能基元中热电和自旋热效应耦合的机理和影响因素；基元序构薄膜中功能基元间的耦合作用以及调控方式，探索序构提高制冷性能的的机制；发现热电磁序构薄膜中由于电子、声子以及自旋之间的耦合所产生的新效应，并探索相关机制。

The ever growing of the integration and power of electronic/photoelectric devices and chips increases the demand for thin films with breakthrough refrigeration performance for device cooling. In this project, ordered magneto-thermo-electric thin films will be built by artificially ordering the functional elements composed of thermoelectric and magnetic thin film units and their thermoelectric properties will be investigated in the aim to explore new methods and new mechanisms to largely enhance the performance of refrigeration. The main research contents include: 1) to construct magneto-thermo-electric composited functional elements using thermoelectric and magnetic thin film units based on proper design and optimization of the compositions and structures of each unit, and perfectly manipulate the interface through proper fabrication process control and fabrication parameter optimization; 2) Based on a comprehensive investigation of the effects of geometric dimensions, shape, position and Curie temperature distributions of the functional elements, to explore the best patterns for the functional elements and develop proper fabrication technologies to realize pattern; 3) To study the thermoelectric properties of the functional element ordered thin films and to develop best methods for property characterization, and investigate the influences of thermoelectric effects, spincaloric effects and magnetoelectric effects the coupling among them, based on which the mechanism for the refrigeration effects in ordered magneto-thermo-electric thin films will be clarified. It is expected to make breakthrough in following three key scientific issues:1) understanding of the coupling between thermoelectric effects and spincaloric effects in thermoelectric-magnetic composed functional elements and clarification of the effects of this coupling on the properties of the elements; 2) getting good knowledge on the coupling among the functional elements and the way for manipulation inter-element coupling, based on which exploring new mechanisms for the enhancement of refrigeration performance;3)discovering the new phenomena and related physics due to the coupling among electrons, phonons and spins in ordered magneto-thermo-electric thin films.