Molecular dynamics study on the dependence of thermal conductivity on size and strain in GaN nanofilms  

作　　者：唐莹 刘俊坤 于子皓 孙李刚 朱林利 Ying Tang;Junkun Liu;Zihao Yu;Ligang Sun;Linli Zhu(College of Optics and Electronics Technology,China Jiliang University,Hangzhou 310018,China;Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province,School of Aeronautics and Astronautics,Zhejiang University,Hangzhou 310027,China;School of Science,Harbin Institute of Technology,Shenzhen 518055,China)

机构地区：[1]College of Optics and Electronics Technology,China Jiliang University,Hangzhou 310018,China [2]Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province,School of Aeronautics and Astronautics,Zhejiang University,Hangzhou 310027,China [3]School of Science,Harbin Institute of Technology,Shenzhen 518055,China

出　　处：《Chinese Physics B》2023年第6期454-458,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11772294 and 11621062);the Fundamental Research Funds for the Central Universities(Grant No.2017QNA4031)。

摘　　要：The thermal conductivity of GaN nanofilm is simulated by using the molecular dynamics(MD)method to explore the influence of the nanofilm thickness and the pre-strain field under different temperatures.It is demonstrated that the thermal conductivity of GaN nanofilm increases with the increase of nanofilm thickness,while decreases with the increase of temperature.Meanwhile,the thermal conductivity of strained GaN nanofilms is weakened with increasing the tensile strain.The film thickness and environment temperature can affect the strain effect on the thermal conductivity of GaN nanofilms.In addition,the analysis of phonon properties of GaN nanofilm shows that the phonon dispersion and density of states of GaN nanofilms can be significantly modified by the film thickness and strain.The results in this work can provide the theoretical supports for regulating the thermal properties of GaN nanofilm through tailoring the geometric size and strain engineering.

关 键 词：molecular dynamics simulation GaN nanofilm thermal conductivity phonon properties size effect strain effect 

分 类 号：TN304[电子电信—物理电子学]