文献类型：期刊文献

英文题名：Phonon anharmonicities in 7-armchair graphene nanoribbons

作者：Guo, Xiao[1];Tian, Qiwei[2];Wang, Yongsong[1];Liu, Jinxin[1];Jia, Guiping[1];Dou, Weidong[3];Song, Fei[4];Zhang, Lijie[2];Qin, Zhihui;Huang, Han[1]

机构：[1]Cent South Univ, Sch Phys & Elect, Hunan Key Lab Supermicrostruct & Ultrafast Pro, Changsha 410083, Peoples R China;[2]Hunan Univ, Minist Educ, Sch Phys & Elect, Key Lab MicroNano Optoelect Devices,Hunan Prov Ke, Changsha 410082, Peoples R China;[3]Shaoxing Univ, Dept Phys, Shaoxing 312000, Peoples R China;[4]Chinese Acad Sci, Shanghai Inst Appl Phys, Shanghai Synchrotron Radiat Facil, 239 Zhangheng Rd,Pudong New Area, Shanghai 201204, Peoples R China

年份：2022

卷号：190

起止页码：312

外文期刊名：CARBON

收录：SCI-EXPANDED(收录号：WOS:000760357400005)、、EI(收录号：20220411491797)、Scopus(收录号：2-s2.0-85122994530)、WOS

基金：We acknowledge the financial support from the National Natural Science Foundation (NSF) of China (Grants No. 11874427, 11304398, 51772087) and the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB30000000) .

语种：英文

外文关键词：On-surface synthesis; Phonon anharmonicity; Temperature coef ficient; RBLM; STM

外文摘要：Graphene nanoribbons (GNRs) provide a potential alternative to overcome the shortcoming of gapless graphene and have been applied into next-generation nanoelectronic devices like FETs. The phonon anharmonicities in functional materials usually play a key role in the device performance. Here, temperature dependent Raman scattering measurements on high quality 7-armchair GNRs (7-AGNRs) on Au(111) synthesized by on-surface method were conducted in the temperature range from 80 to 520 K. The frequency of optical phonon G mode (collective acoustic phonon RBLM mode) linearly (nonlinearly) downshifts with temperature. The first-order temperature coefficient of G mode of 7-AGNR is calculated to be -0.026 cm-1K-1, almost twice that of freestanding graphene of -0.015 cm-1K-1 and half of that of CVD grown single layer graphene on Cu foils of -0.056 cm-1K-1. For RBLM, the anharmonicity is much weaker and attributed to the intrinsic quartic-phonon decay processes rather than the cubic-phonon ones. Our findings make a first step to the thermal properties of atomically precise GNRs. (c) 2022 Elsevier Ltd. All rights reserved.