孔洞缺陷对二维石墨烯/氮化硼横向异质结热传导的调控  

The control of thermal conductivity in two-dimensional graphene / hexagonalboron nitride lateral heterostructures by pore defects

作　　者：翟方园 张定波 曹增强 黄晓宇 倪宇翔 王红艳[1] 张文婷 ZHAI Fang-Yuan;ZHANG Ding-Bo;CAO Zeng-Qiang;HUANG Xiao-Yu;NI Yu-Xiang;WANG Hong-Yan;ZHANG Wen-Ting(School of Physical Science and Technology,Southwest Jiaotong University,Chengdu 611700,China)

机构地区：[1]西南交通大学物理科学与技术学院,成都611700

出　　处：《原子与分子物理学报》2024年第6期66-71,共6页Journal of Atomic and Molecular Physics

摘　　要：本文采用孔洞缺陷来实现对二维石墨烯/氮化硼横向异质结热导率的调控.平衡态分子动力学(EMD)计算结果表明,界面孔洞的引入会降低二维石墨烯/氮化硼横向异质结的热导率.相较于有序的孔洞分布,无序的孔洞分布能够更有效地降低异质结的热导率,这一现象可通过声子安德森局域化来解释.孔洞缺陷的存在导致声子的频率和波失发生变化,从而使声子散射变得更加频繁,孔洞随机分布时,则导致声子波在材料中发生多次反射和散射,最终形成局域振动模式.本研究揭示了孔洞缺陷降低二维石墨烯/氮化硼横向异质结热导率的物理机制,对二维热电材料的结构设计有一定的指导意义.This article uses void defects to regulate the thermal conductivity of the two-dimensional graphene/h-BN lateral heterojunction. The results of equilibrium molecular dynamics (EMD ) calculations show that the introduction of interface voids can reduce the thermal conductivity of the heterojunction. Compared with the ordered void distribution, the disordered void distribution can more effectively reduce the thermal conductivity of the heterojunction, which can be explained by phonon Anderson localization. The presence of void defects leads to changes in the frequency and wave vector of phonons, making phonon scattering more frequent. When voids are randomly distributed, phonon waves undergo multiple reflections and scattering in the material, eventually forming localized vibrational modes. This study reveals the physical mechanism by which void defects reduce the thermal conductivity of the two-dimensional graphene/h-BN lateral heterojunction and has some guiding significance for the structural design of two-dimensional thermoelectric materials.

关 键 词：石墨烯/氮化硼 热输运 分子动力学 安德森声子局域化 

分 类 号：O64[理学—物理化学]