J. Mater. Sci. Technol. ›› 2025, Vol. 207: 70-75.DOI: 10.1016/j.jmst.2024.04.029

• Research article • Previous Articles     Next Articles

Electrically tunable Γ-Q interlayer excitons in twisted MoSe2 bilayers

Jinqiang Huanga,b,1, Zhiren Xiongc,d,1, Jinkun Hec,d,1, Xingguang Wuc,d, Kenji Watanabee, Takashi Taniguchif, Shen Laig, Tongyao Zhangc,d,h,*, Zheng Vitto Hanc,d,h,*, Siwen Zhaoh,*   

  1. aResearch, Chinese Academy of Sciences, Shenyang, 110016, China;
    bSchool of Material Science and Engineering, University of Science and Technology of China, Shenyang, 110016, China;
    cState Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Optoelectronics, Shanxi University, Taiyuan, 030006, China;
    dCollaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China;
    eResearch Center for Electronic and Optical Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan;
    fResearch Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan;
    gInstitute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau SAR, 999078, China;
    hLiaoning Academy of Materials, Shenyang, China;
    iHefei National Laboratory, Hefei, 230088, China
  • Received:2024-02-08 Revised:2024-04-24 Accepted:2024-04-26 Published:2025-02-01 Online:2024-05-07
  • Contact: *E-mail addresses: tongyao_zhang@sxu.edu.cn (T. Zhang), vitto.han@gmail.com (Z.V. Han), siwenzhao0126@gmail.com (S. Zhao)
  • About author:1 These authors contributed equally to this work.

Abstract: Twist, the very degree of freedom in van der Waals heterostructures, offers a compelling avenue to manipulate and tailor their electrical and optical characteristics. In particular, moiré patterns in twisted homobilayer transition metal dichalcogenides (TMDs) lead to zone folding and miniband formation in the resulting electronic bands, holding the promise to exhibit inter-layer excitonic optical phenomena. Although some experiments have shown the existence of twist-angle-dependent intra- and inter-layer excitons in twisted MoSe2 homobilayers, electrical control of the interlayer excitons in MoSe2 is relatively under-explored. Here, we show the signatures of the moiré effect on intralayer and interlayer excitons in 2H-stacked twisted MoSe2 homobilayers. Doping- and electric field-dependent photoluminescence measurements at low temperatures give evidence of the momentum-direct K-K intralayer excitons, and the momentum-indirect Γ-K and Γ-Q interlayer excitons. Our results suggest that twisted MoSe2 homobilayers are an intriguing platform for engineering interlayer exciton states, which may shed light on future atomically thin optoelectronic applications.

Key words: Interlayer excitons, Intralayer excitons, Twisted bilayer TMDs, Momentum indirect excitons