The modulation of terahertz photoconductivity in CVD grown n-doped monolayer MoS2 with gas adsorption. (2nd April 2019)

• Record Type: Journal Article
• Authors: Xing, Xiao; Zhao, Litao; Zhang, Zeyu; Lin, Xian; Yu, Yang; Jin, Zuanming; Liu, Weimin; Zhang, Wenjing; Ma, Guohong
• Is Part Of: Journal of physics. Volume 31:Number 24(2019)
• Publication Date: 2019-04-02
• Subjects: transition metal dichalcogenides -- terahertz photoconductivity -- trions -- oxygen passivation; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/ab0f0a
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: The as-grown atomically thin transition metal dichalcogenides (TMDs) usually have extremely large surface-to-volume ratios. Hence, the electrical and optical properties are always affected by the adsorption of atmospheric gases. By using optical pump terahertz (THz) probe spectroscopy, THz photoconductivity dynamics of chemical vapor deposition grown monolayer MoS2 has been investigated in nitrogen, air and oxygen atmospheric environments. Our study reveals that the photoconductivity of MoS2 at THz frequencies is dramatically altered by the adsorption of oxygen. The relaxation dynamics of photoconductivity strongly depends on atmospheres, which is attributed to photo-excited different quasi-particles, such as free charge carriers, excitons and trions. This study highlights the role of oxygen passivation of the photoconductivity in monolayer MoS2, which may have important applications for the design of future MoS2 -based electronic devices.