基于二硫化钼的可调一维声子晶体  

Tunable One-dimensional Phononic Crystals Based on Molybdenum Disulfide

作　　者：张庆航 ZHANG Qinghang(University of Science and Technology,CAS key Laboratory of Quantum Information,Hefei 230026)

机构地区：[1]中国科学技术大学,中国科学院量子信息重点实验室,合肥230026

出　　处：《低温物理学报》2021年第2期130-134,共5页Low Temperature Physical Letters

摘　　要：声子晶体所具有的负折射率、局域缺陷态与弹性波带隙等特性,使其在声学隐身、声学波导以及减震降噪等方向展现了巨大的潜力.同时,二硫化钼优异的电学和力学性能使其成为制备纳米机电器件的理想材料.将单层二硫化钼转移到预先图案化的周期性结构上,可以制备出纳米尺度的声子晶体器件.本文设计了一种通过将单层二硫化钼转移贴合在预先制备的周期性沟槽阵列上,形成一维声子晶体的方案.有限元分析表明,这种声子晶体在MHz范围存在声子能带结构,可以实现对声波传播的控制.我们可以通过改变结构参数,或者通过改变施加在栅电极上的电压,对能带进行调控.这种结构为开发基于二维材料的纳米尺度的声子晶体器件提供了可能性.Phononic crystals(PnCs)have shown great potentials in applications such as acoustic stealth,acoustic waveguide,and noise reduction due to their excellent characteristics including negative refractive index,local defect state and elastic band structure.Meanwhile,the excellent electrical and mechanical properties make molybdenum disulfide a promising material for nanoelectromechanical resonators.Transferring a molybdenum disulfide flake to a pre-patterned periodic mechanical structure enables realization of PnCs with on-chip scale.Here,we propose a way for realizing one-dimensional PnCs by anchoring a molybdenum disulfide membrane to a pre-patterned trench.Finite element analysis shows that such design of PnC has a phononic band structure in the frequency range of~MHz,allowing the control of acoustic wave propagation.By varying the structure parameters or changing the voltage applied to the gate electrode,the phononic band can be tuned.This architecture provides the possibility for the development of phononic crystal devices at nanoscale based on two-dimensional materials.

关 键 词：二硫化钼 纳米机电谐振器 声子晶体 可调 

分 类 号：O735[理学—晶体学] TQ136.12[化学工程—无机化工]