利用变温拉曼光谱和光致发光光谱发现的堆叠式MoS/TaS异质结构的层间耦合及相变机制。

Interlayer coupling and the phase transition mechanism of stacked MoS/TaS heterostructures discovered using temperature dependent Raman and photoluminescence spectroscopy.

作者信息

Chen Miao, Zhou Bin, Wang Fang, Xu Liping, Jiang Kai, Shang Liyan, Hu Zhigao, Chu Junhao

机构信息

Key Laboratory of Polar Materials and Devices (MOE), Technical Center for Multifunctional Magneto-Optical Spectroscopy (Shanghai), Department of Electronic Engineering, East China Normal University Shanghai 200241 China

Collaborative Innovation Center of Extreme Optics, Shanxi University Taiyuan Shanxi 030006 China.

出版信息

RSC Adv. 2018 Jun 14;8(39):21968-21974. doi: 10.1039/c8ra03436b. eCollection 2018 Jun 13.

DOI:10.1039/c8ra03436b

PMID:35541734

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC9081101/

Abstract

Ultrathin 1T (tetragonal)-TaS and monolayer MoS heterostructures were prepared to study their phase transition (PT) mechanisms and band structure modulation. The temperature dependency of photoluminescence (PL) and Raman spectra was utilized to study interlayer coupling and band structure. The PL results indicate that the band structure of MoS/TaS heterostructures undergoes a sharp change at 214 K. This is attributed to the PT of 1T-TaS from a Mott insulator state to a metastable state. In addition, the temperature dependency of the MoS/TaS Raman spectra illustrates that the phonon vibration of the heterojunction is softened due to the effect of interlayer coupling. The present work could provide an avenue to create material systems with abundant functionalities and physical effects.

摘要

制备了超薄的1T（四方相）-TaS和单层MoS异质结构，以研究它们的相变（PT）机制和能带结构调制。利用光致发光（PL）和拉曼光谱的温度依赖性来研究层间耦合和能带结构。PL结果表明，MoS/TaS异质结构的能带结构在214 K时发生急剧变化。这归因于1T-TaS从莫特绝缘态到亚稳态的相变。此外，MoS/TaS拉曼光谱的温度依赖性表明，由于层间耦合的影响，异质结的声子振动变软。目前的工作可以为创建具有丰富功能和物理效应的材料系统提供一条途径。