Dong H M, Tao Z H, Duan Y F, Huang F, Zhao C X
School of Physical Science and Technology, China University of Mining and Technology, Xuzhou 221116, People's Republic of China.
J Phys Condens Matter. 2020 Mar 20;32(12):125703. doi: 10.1088/1361-648X/ab5907. Epub 2019 Nov 19.
We present a theoretical study of the plasmon-phonon coupling in a suspended monolayer MoS and a MoS substrate system using a diagrammatic self-consistent field theory. The four coupled plasmon-phonon modes and the four plasmon-surface phonon modes are observed due to the spin-orbit and electron-optic phonon interactions. The two of coupled plasmon-phonon and plasmon-surface phonon modes are optic-like and the other two are acoustic-like. The plasmon are strongly coupled with the optic-phonon in MoS and the surface optic-phonon in the substrates as the electron density or wave-vector increases. The strong plasmon-phonon coupling shows that the optoelectronic properties of monolayer MoS are evidently modulated by electron-phonon interactions. The hybrid plasmon-phonon polaritons can be achieved by strong light-mater interactions. This study is relevant to the application of MoS as novel plasmonic and nanophotonic devices.
我们使用图解自洽场理论对悬浮单层MoS和MoS衬底系统中的等离激元-声子耦合进行了理论研究。由于自旋轨道和电子-光学声子相互作用，观察到了四种耦合等离激元-声子模式和四种等离激元-表面声子模式。耦合等离激元-声子模式和等离激元-表面声子模式中的两种是类光学模式，另外两种是类声学模式。随着电子密度或波矢增加，等离激元与MoS中的光学声子以及衬底中的表面光学声子强烈耦合。强等离激元-声子耦合表明，单层MoS的光电特性明显受到电子-声子相互作用的调制。通过强光-物质相互作用可以实现混合等离激元-声子极化激元。本研究与MoS作为新型等离激元和纳米光子器件的应用相关。
