Ultrafast Terahertz Complex Conductivity Dynamics of Layered MoS2 Crystal Probed by Time-Resolved Terahertz Spectroscopy
Ultrafast carrier dynamics, including the carrier photoexcitation and relaxation processes, plays an essential role in improving the performance of molybdenum disulfide (MoS2)-based optoelectronic devices. Herein, we investigate the photo-generated carrier dynamics in layered MoS2 crystal using a ti...
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| Language: | English |
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Frontiers Media S.A.
2021-10-01
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| Series: | Frontiers in Physics |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fphy.2021.764122/full |
| _version_ | 1818930929611046912 |
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| author | Yong Yang Chuan He Yuanyuan Huang Lipeng Zhu Yixuan Zhou Xinlong Xu |
| author_facet | Yong Yang Chuan He Yuanyuan Huang Lipeng Zhu Yixuan Zhou Xinlong Xu |
| author_sort | Yong Yang |
| collection | DOAJ |
| description | Ultrafast carrier dynamics, including the carrier photoexcitation and relaxation processes, plays an essential role in improving the performance of molybdenum disulfide (MoS2)-based optoelectronic devices. Herein, we investigate the photo-generated carrier dynamics in layered MoS2 crystal using a time-resolved terahertz (THz) spectroscopy. We have analyzed the ultrafast changes of the THz complex photoconductivity deduced from the peak and zero-crossing of THz waveforms. The decay time of the real part of the THz photoconductivity in layered MoS2 crystal is independent with the pump power, while the imaginary part increases with the pump power. We attribute the decay time of the real part to the carrier recombination process via phonon-assistance and the decay time of the imaginary part to the defect-assisted exciton recombination. The peak values of the complex photoconductivity show a trend of saturation with the increase of the pump power because of the many-body effect at high carrier concentration. This work deepens the understanding of the basic ultrafast physical process in MoS2 crystal, which is enlightening for the design of novel optoelectronic devices. |
| first_indexed | 2024-12-20T04:08:30Z |
| format | Article |
| id | doaj.art-c8cb87d46012478899e33b6ac131f867 |
| institution | Directory Open Access Journal |
| issn | 2296-424X |
| language | English |
| last_indexed | 2024-12-20T04:08:30Z |
| publishDate | 2021-10-01 |
| publisher | Frontiers Media S.A. |
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| series | Frontiers in Physics |
| spelling | doaj.art-c8cb87d46012478899e33b6ac131f8672022-12-21T19:53:59ZengFrontiers Media S.A.Frontiers in Physics2296-424X2021-10-01910.3389/fphy.2021.764122764122Ultrafast Terahertz Complex Conductivity Dynamics of Layered MoS2 Crystal Probed by Time-Resolved Terahertz SpectroscopyYong Yang0Chuan He1Yuanyuan Huang2Lipeng Zhu3Yixuan Zhou4Xinlong Xu5Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, School of Physics, Institute of Photonics and Photon-Technology, Northwest University, Xi’an, ChinaShaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, School of Physics, Institute of Photonics and Photon-Technology, Northwest University, Xi’an, ChinaShaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, School of Physics, Institute of Photonics and Photon-Technology, Northwest University, Xi’an, ChinaSchool of Electronic Engineering, Xi’an University of Posts and Telecommunications, Xi’an, ChinaShaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, School of Physics, Institute of Photonics and Photon-Technology, Northwest University, Xi’an, ChinaShaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, School of Physics, Institute of Photonics and Photon-Technology, Northwest University, Xi’an, ChinaUltrafast carrier dynamics, including the carrier photoexcitation and relaxation processes, plays an essential role in improving the performance of molybdenum disulfide (MoS2)-based optoelectronic devices. Herein, we investigate the photo-generated carrier dynamics in layered MoS2 crystal using a time-resolved terahertz (THz) spectroscopy. We have analyzed the ultrafast changes of the THz complex photoconductivity deduced from the peak and zero-crossing of THz waveforms. The decay time of the real part of the THz photoconductivity in layered MoS2 crystal is independent with the pump power, while the imaginary part increases with the pump power. We attribute the decay time of the real part to the carrier recombination process via phonon-assistance and the decay time of the imaginary part to the defect-assisted exciton recombination. The peak values of the complex photoconductivity show a trend of saturation with the increase of the pump power because of the many-body effect at high carrier concentration. This work deepens the understanding of the basic ultrafast physical process in MoS2 crystal, which is enlightening for the design of novel optoelectronic devices.https://www.frontiersin.org/articles/10.3389/fphy.2021.764122/fulllayered MoS2 crystaltime-resolved terahertz spectroscopyultrafast carrier dynamicsexciton dynamicsterahertz photoconductivity |
| spellingShingle | Yong Yang Chuan He Yuanyuan Huang Lipeng Zhu Yixuan Zhou Xinlong Xu Ultrafast Terahertz Complex Conductivity Dynamics of Layered MoS2 Crystal Probed by Time-Resolved Terahertz Spectroscopy Frontiers in Physics layered MoS2 crystal time-resolved terahertz spectroscopy ultrafast carrier dynamics exciton dynamics terahertz photoconductivity |
| title | Ultrafast Terahertz Complex Conductivity Dynamics of Layered MoS2 Crystal Probed by Time-Resolved Terahertz Spectroscopy |
| title_full | Ultrafast Terahertz Complex Conductivity Dynamics of Layered MoS2 Crystal Probed by Time-Resolved Terahertz Spectroscopy |
| title_fullStr | Ultrafast Terahertz Complex Conductivity Dynamics of Layered MoS2 Crystal Probed by Time-Resolved Terahertz Spectroscopy |
| title_full_unstemmed | Ultrafast Terahertz Complex Conductivity Dynamics of Layered MoS2 Crystal Probed by Time-Resolved Terahertz Spectroscopy |
| title_short | Ultrafast Terahertz Complex Conductivity Dynamics of Layered MoS2 Crystal Probed by Time-Resolved Terahertz Spectroscopy |
| title_sort | ultrafast terahertz complex conductivity dynamics of layered mos2 crystal probed by time resolved terahertz spectroscopy |
| topic | layered MoS2 crystal time-resolved terahertz spectroscopy ultrafast carrier dynamics exciton dynamics terahertz photoconductivity |
| url | https://www.frontiersin.org/articles/10.3389/fphy.2021.764122/full |
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