Lattice Thermal Conductivity of MgSiO_(3) Perovskite and Post-Perovskite under Lower Mantle Conditions Calculated by Deep Potential Molecular Dynamics  

作　　者：Fenghu Yang Qiyu Zeng Bo Chen Dongdong Kang Shen Zhang Jianhua Wu Xiaoxiang Yu Jiayu Dai 杨凤虎;曾启昱;陈博;康冬冬;张珅;吴建华;余晓翔;戴佳钰(Department of Physics,National University of Defense Technology,Changsha 410003,China)

机构地区：[1]Department of Physics,National University of Defense Technology,Changsha 410003,China

出　　处：《Chinese Physics Letters》2022年第11期42-47,共6页中国物理快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.U1830206);the National Key R&D Program of China(Grant No.2017YFA0403200);the National Natural Science Foundation of China(Grant Nos.11874424,11904401,11974423,and 12104507);the Science and Technology Innovation Program of Hunan Province(Grant No.2021RC4026)。

摘　　要：Lattice thermal conductivity(κlat)of MgSiO_(3) perovskite and post-perovskite is an important parameter for the thermal dynamics in the Earth.Here,we develop a deep potential of density functional theory quality under entire thermodynamic conditions in the lower mantle,and calculate theκlatby the Green-Kubo relation.Deep potential molecular dynamics captures full-order anharmonicity and considers ill-defined phonons in low-κlatmaterials ignored in the phonon gas model.Theκlatshows negative temperature dependence and positive linear pressure dependence.Interestingly,theκlatundergos an increase at the phase boundary from perovskite to post-perovskite.We demonstrate that,along the geotherm,theκlatincreases by 18.2% at the phase boundary.Our results would be helpful for evaluating Earth’s thermal dynamics and improving the Earth model.

关 键 词：LATTICE PEROVSKITE DEEP 

分 类 号：P575[天文地球—矿物学]