BROWSE

Related Scientist

CINAP's photo.

CINAP
나노구조물리 연구단
more info

ITEM VIEW & DOWNLOAD

Unusually large exciton binding energy in multilayered 2H-MoTe2

Cited 0 time in webofscience Cited 0 time in scopus
235 Viewed 0 Downloaded
Title
Unusually large exciton binding energy in multilayered 2H-MoTe2
Author(s)
Eilho Jung; Jin Cheol Park; Seo, Yu-Seong; Ji-Hee Kim; Hwang, Jungseek; Young Hee Lee
Publication Date
2022-03
Journal
SCIENTIFIC REPORTS, v.12, no.1
Publisher
NATURE PORTFOLIO
Abstract
© 2022 Springer Nature Limited. Although large exciton binding energies of typically 0.6-1.0 eV are observed for monolayer transition metal dichalcogenides (TMDs) owing to strong Coulomb interaction, multilayered TMDs yield relatively low exciton binding energies owing to increased dielectric screening. Recently, the ideal carrier-multiplication threshold energy of twice the bandgap has been realized in multilayered semiconducting 2H-MoTe2 with a conversion efficiency of 99%, which suggests strong Coulomb interaction. However, the origin of strong Coulomb interaction in multilayered 2H-MoTe2, including the exciton binding energy, has not been elucidated to date. In this study, unusually large exciton binding energy is observed through optical spectroscopy conducted on CVD-grown 2H-MoTe2. To extract exciton binding energy, the optical conductivity is fitted using the Lorentz model to describe the exciton peaks and the Tauc-Lorentz model to describe the indirect and direct bandgaps. The exciton binding energy of 4 nm thick multilayered 2H-MoTe2 is approximately 300 meV, which is unusually large by one order of magnitude when compared with other multilayered TMD semiconductors such as 2H-MoS2 or 2H-MoSe2 . This finding is interpreted in terms of small exciton radius based on the 2D Rydberg model. The exciton radius of multilayered 2H-MoTe2 resembles that of monolayer 2H-MoTe2, whereas those of multilayered 2H-MoS2 and 2H-MoSe2 are large when compared with monolayer 2H-MoS2 and 2H-MoSe2. From the large exciton binding energy in multilayered 2H-MoTe2, it is expected to realize the future applications such as room-temperature and high-temperature polariton lasing.
URI
https://pr.ibs.re.kr/handle/8788114/11582
DOI
10.1038/s41598-022-08692-1
ISSN
2045-2322
Appears in Collections:
Center for Integrated Nanostructure Physics(나노구조물리 연구단) > 1. Journal Papers (저널논문)
Files in This Item:
There are no files associated with this item.

qrcode

  • facebook

    twitter

  • Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.
해당 아이템을 이메일로 공유하기 원하시면 인증을 거치시기 바랍니다.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Browse