笼状物I型clathrate材料以其特殊的主客体笼状结构,同时具有非常低的晶格热导率和相对较高的载流子迁移率，被认为是应用前景良好的新型热电材料。其特殊的笼状结构导致了众多有趣的物理现象，如复杂的晶体结构下的能带调控、单势阱非简谐振动-多势阱非简谐振动转变、接近理论极限的低晶格热导率和非简谐振动情况下的电声子相互作用等。然而，这些对热电性能调节至关重要的的物理机制仍然没有被完全理解。本项目从晶体生长出发，采用新方法合成新型高质量clathrate单晶材料，在研究clathrate材料本征物理性质的基础上，探索材料中过渡族元素对能带结构和晶格热导率的调控机制，以及非简谐振动下的电声子相互作用对载流子的影响，为设计高性能的热电材料与了解材料中的非简谐振动理论提供关键实验信息。

Type I clathrate compounds, which have unique cage-like structures, have very low lattice thermal conductivity and relatively high carrier mobility at the same time. Therefore, they are to be potential high performance thermoelectric materials. Due to the unique structure, lots of interesting physical phenomena have been observed, such as band structure engineering in the complicate structure, the transition between single well anharmonic potential and mutli-wells anharmonic potential, low lattice thermal conductivity close to theoretical limit, electron-phonon interactions of the anharmonic phonons, and so on. However, the mechanisms to control these properties are still not understood. In this project, based on high quality single crystals growth by new methods, the intrinsic physical properties will be studied, to understand the contributions of the transition metals to the band structure and lattice thermal conductivity, as well as the effect of electron-phonon interactions by the anharmonic phonons on the electrical properties.