Strong interface scattering induced low thermal conductivity in Bi-based GeTe/Bi2Te3 superlattice-like materials

Yang Zhou; Kaijin Huang; Lingjun Zhou; Xiaomin Cheng; Ming Xu; Hao Tong; Xiangshui Miao

doi:10.1039/c9ra01485c

Strong interface scattering induced low thermal conductivity in Bi-based GeTe/Bi₂Te₃ superlattice-like materials

RSC Adv. 2019 Mar 25;9(17):9457-9461. doi: 10.1039/c9ra01485c. eCollection 2019 Mar 22.

Authors

Yang Zhou¹, Kaijin Huang¹, Lingjun Zhou¹, Xiaomin Cheng¹, Ming Xu¹, Hao Tong¹, Xiangshui Miao¹

Affiliation

¹ Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology Wuhan 430074 China tonghao@hust.edu.cn.

Abstract

The thermal conductivities of GeTe/Bi₂Te₃ superlattice-like materials are calculated based on density functional perturbation theory (DFPT) and measured using a 3ω method. The calculated results show that the lattice thermal conductivity or thermal diffusivity of GeTe/Bi₂Te₃ superlattice-like materials significantly decrease due to the effects of interfaces and Bi atoms in Bi₂Te₃. Our measured results are in line with the theoretical calculations, and reach an extremely low thermal conductivity at 0.162 W mK^-1 compared with published work on Ge-Sb(Bi)-Te, indicating the effectiveness of modulating the thermal properties of phase change materials by using Bi-based GeTe/Bi₂Te₃ superlattice-like materials. Our findings give a calculation method to modify the thermal characteristics of superlattice-like materials and confirm Bi-based GeTe/Bi₂Te₃ superlattice-like materials as promising candidates for phase change materials with lower thermal conductivity.