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Stacking single layers of atoms on top of each other provides a fundamental way to achieve novel material systems and engineer their physical properties, which offers opportunities for exploring fundamental physics and realizing next-generation optoelectronic devices. Among the two-dimensional (2D)-stacked systems, transition metal dichalcogenide (TMDC) heterostructures are particularly attractive because they host tightly-bonded interlayer excitons which possess various novel and appealing properties. These interlayer excitons have drawn significant research attention and hold high potential for the application in unique optoelectronic devices, such as polarization- and wavelength-tunable single photon emitters, valley Hall transistors, and possible high-temperature superconductors. The development of these devices requires a comprehensive understanding of the fundamental properties of these interlayer excitons and the impact of electric fields on their behaviors. In this review, we summarize the recent advances on the understanding of interlayer exciton dynamics under electric fields in TMDC heterostructures. We put emphasis on the electrical modulation of interlayer excitons’ emission, the valley Hall transport of charge carriers after the separation of interlayer excitons by an electric field, and the correlation physics of interlayer excitons and charges under electrical doping and tuning. Challenges and perspectives are finally discussed for the application of TMDC heterostructures in future optoelectronics.


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Interlayer exciton dynamics of transition metal dichalcogenide heterostructures under electric fields

Show Author's information Jian Tang1Yue Zheng1Ke Jiang1Qi You1Zhentian Yin1Zihao Xie1Henan Li2Cheng Han1( )Xiaoxian Zhang3( )Yumeng Shi2( )
International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
College of Electronics and Information Engineering, Shenzhen University, Shenzhen 518060, China
Key Laboratory of Luminescence and Optical Information, Ministry of Education, Institute of Optoelectronic Technology, Beijing Jiaotong University, Beijing 100044, China

Abstract

Stacking single layers of atoms on top of each other provides a fundamental way to achieve novel material systems and engineer their physical properties, which offers opportunities for exploring fundamental physics and realizing next-generation optoelectronic devices. Among the two-dimensional (2D)-stacked systems, transition metal dichalcogenide (TMDC) heterostructures are particularly attractive because they host tightly-bonded interlayer excitons which possess various novel and appealing properties. These interlayer excitons have drawn significant research attention and hold high potential for the application in unique optoelectronic devices, such as polarization- and wavelength-tunable single photon emitters, valley Hall transistors, and possible high-temperature superconductors. The development of these devices requires a comprehensive understanding of the fundamental properties of these interlayer excitons and the impact of electric fields on their behaviors. In this review, we summarize the recent advances on the understanding of interlayer exciton dynamics under electric fields in TMDC heterostructures. We put emphasis on the electrical modulation of interlayer excitons’ emission, the valley Hall transport of charge carriers after the separation of interlayer excitons by an electric field, and the correlation physics of interlayer excitons and charges under electrical doping and tuning. Challenges and perspectives are finally discussed for the application of TMDC heterostructures in future optoelectronics.

Keywords: interlayer exciton, valley Hall effect, strong coupling, circular polarization, transition metal dichalcogenide (TMDC) heterostructures

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Publication history
Copyright
Acknowledgements

Publication history

Received: 28 August 2023
Revised: 20 October 2023
Accepted: 07 November 2023
Published: 07 December 2023
Issue date: May 2024

Copyright

© Tsinghua University Press 2023

Acknowledgements

Acknowledgements

Y. M. S., C. H., and X. X. Z. acknowledge the support from the National Natural Science Foundation of China (Nos. 61874074, 62004128, and 11974088) and Science and Technology Project of Shenzhen (No. JCYJ20220531100815034). J. T. acknowledges the support from China Postdoctoral Science Foundation (No. 2020M682847). H. N. L. acknowledges Guangdong Basic and Applied Basic Research Foundation (General Program, No. 2022A1515012055).

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