Article Momentum-forbidden dark excitons in hBN-encapsulated monolayer MoS2

Yosuke Uchiyama ; Alex Kutana ; Kenji Watanabe SAMURAI ORCID ; Takashi Taniguchi SAMURAI ORCID ; Kana Kojima ; Takahiko Endo ; Yasumitsu Miyata ; Hisanori Shinohara ; Ryo Kitaura SAMURAI ORCID (National Institute for Materials Science)

s41699-019-0108-4.pdf
Download all files
(1.46 MB)
Collection

Citation
Yosuke Uchiyama, Alex Kutana, Kenji Watanabe, Takashi Taniguchi, Kana Kojima, Takahiko Endo, Yasumitsu Miyata, Hisanori Shinohara, Ryo Kitaura. Momentum-forbidden dark excitons in hBN-encapsulated monolayer MoS2. npj 2D Materials and Applications. 2019, 3 (1), 26.
SAMURAI

Description:

(abstract)

We present measurements of temperature dependence of photoluminescence intensity from monolayer MoS2 encapsulated by hexagonal boron nitride (hBN) flakes. The obtained temperature dependence shows an opposite trend to that of previously observed in a monolayer MoS2 on a SiO2 substrate. Ab-initio bandstructure calculations have revealed that monolayer MoS2 encapsulated by hBN flakes have no longer a direct-gap semiconductor but an indirect-gap semiconductor. This is caused by orbital hybridization between MoS2 and hBN, which leads to upward shift of gamma-valley of MoS2. This work shows an important implication that the hBN-encapsulation structure used to address intrinsic properties of two-dimensional crystals can alter basic properties encapsulated materials in some cases.

Rights:

Keyword: Hexagonal boron nitride, photoluminescence, dark excitons

Date published: 2019-07-19

Publisher: Springer Science and Business Media LLC

Journal:

  • npj 2D Materials and Applications (ISSN: 23977132) vol. 3 issue. 1 26

Funding:

  • MEXT | Japan Society for the Promotion of Science JP16H06331
  • MEXT | Japan Society for the Promotion of Science JP15K13283
  • MEXT | JST | Core Research for Evolutional Science and Technology JPMJCR16F3

Manuscript type: Publisher's version (Version of record)

MDR DOI:

First published URL: https://doi.org/10.1038/s41699-019-0108-4

Related item:

Other identifier(s):

Contact agent:

Updated at: 2025-02-23 22:50:08 +0900

Published on MDR: 2025-02-23 22:50:08 +0900

Filename Size
Filename s41699-019-0108-4.pdf (Thumbnail)
application/pdf
Size 1.46 MB Detail