Anomalous strain effect on the thermal conductivity of low-buckled two-dimensional silicene

• 作者: Bin Ding Xiaoyan Li Wuxing Zhou Gang Zhang Huajian Gao
• 来源期刊: 国家科学评论（英文版）
• 年，卷（期）: 2021,（9）
• 所属期刊栏目: Special Topic:Lattice-based Cryptography and the Underlying Computational Problems
• 页码范围: 18-26
• 页数: 9页
• 语种: 英文

摘要

The thermal conductivity of two-dimensional materials,such as graphene,typically decreases when tensile strain is applied,which softens their phonon modes.Here,we report an anomalous strain effect on the thermal conductivity of monolayer silicene,a representative low-buckled two-dimensional (LB-2D)material.ReaxFF-based molecular dynamics simulations are performed to show that biaxially stretched monolayer silicene exhibits a remarkable increase in thermal conductivity,by as much as 10 times the freestanding value,with increasing applied strain in the range of[0,0.1],which is attributed to increased contributions from long-wavelength phonons.A further increase in strain in the range of[0.11,0.18]results in a plateau of the thermal conductivity in an oscillatory manner,govemed by a unique dynamic bonding behavior under extreme loading.This anomalous effect reveals new physical insights into the thermal properties of LB-2D materials and may provide some guidelines for designing heat management and energy conversion devices based on such materials.