# Exciton dynamics in marginally twisted <math>  <mrow>    <mi>WS</mi>    <msub>      <mi>e</mi>      <mn>2</mn>    </msub>  </mrow></math> homobilayer: Role of interlayer coupling, phonons,&nbsp;and intervalley scattering

https://mdr.nims.go.jp/datasets/b98cc1f8-4f16-46df-9a7d-b114ded9159a

## File

- [2025A01275G_supplementary materials_r7.docx](https://mdr.nims.go.jp/filesets/6f1012e0-2a33-41be-ac34-8c79d4d559b7/download) ([Detail](https://mdr.nims.go.jp/filesets/6f1012e0-2a33-41be-ac34-8c79d4d559b7.md))
- [2025A01275G_manuscript_khs_r7.docx](https://mdr.nims.go.jp/filesets/574f66e4-49bf-4734-9f9e-de62b8c3c394/download) ([Detail](https://mdr.nims.go.jp/filesets/574f66e4-49bf-4734-9f9e-de62b8c3c394.md))

## Id

b98cc1f8-4f16-46df-9a7d-b114ded9159a

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2026-06-25T07:38:03.223913Z

## Updated at

2026-06-26T08:19:33.293357Z

## Published at

2026-06-26T23:28:01.449207Z

## Doi



## First published url

https://doi.org/10.1103/2whm-6xyv

## Date published

2025-09-04

## Recorded date published

2025-9

## Resource type

journal_article

## Manuscript type

accepted_manuscript

## Collection



## Title

- title: 'Exciton dynamics in marginally twisted <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>WS</mml:mi><mml:msub><mml:mi
    mathvariant="normal">e</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>
    homobilayer: Role of interlayer coupling, phonons, and intervalley scattering'
  title_type: original
  lang: en

## Description

- description: "In moiré materials, excitons serve as optical probes because of the
    sensitivity to both valley-dependent electronic structure and many-body excitonic
    interactions. For angle-tuned twisted bilayers, lattice reconstruction becomes
    significant at marginal twist angles, raising interesting questions about the
    optical characteristics of excitons both in the steady-state and nonequilibrium
    regimes. In this work, we investigate both the steady-state and the ultrafast
    transient exciton behaviors in a twisted WSe2 homobilayer (t-WSe2) using reflection
    contrast, polarization-resolved photoluminescence, and ultrafast pump–probe spectroscopy.
    We report the emergence of two distinct intralayer excitons in the lattice reconstructed
    t-WSe2, which are used to probe local electronic asymmetries and interlayer coupling
    in moiré domains. These excitons possess distinct temperature- and doping-dependent
    valley coherence and population dynamics, arising from the asymmetric interlayer
    coupling. Theoretical modeling via the Lindblad master equation highlights that
    the pure dephasing rate increases with hole doping, attributed to the enhanced
    electron-hole interactions. Ultrafast degenerate pump-probe spectroscopy reveals
    distinct fast decaying dynamics (<1 ps) for the two intralayer excitonic absorption
    species, \U0001D44B1 and \U0001D44B2, where the asymmetric interlayer coupling
    contributes more to the faster \U0001D44B1 decay than \U0001D44B2. Optical-pump
    and white-light probe spectroscopy further unveils a biexponential decay, where
    the fast component (\U0001D70Ffast≈0.7–0.9ps) signifies rapid radiative recombination
    with repopulation effects in the optical light cone. The slow component (\U0001D70Fslow≈100–300ps)
    is linked to exciton-phonon scattering and population relaxation via interlayer
    breathing phonons. We also present that intervalley scattering pathways, i.e.,
    mediated by the \U0001D43E⁢\U0001D444 transitions, are distinct from the monolayer
    counterpart. This work provides detailed insights into the exciton population
    dynamics in twisted homobilayers, highlighting the role of intervalley and exciton-phonon
    interactions in the transient multiple exciton complex behaviors."
  description_type: abstract
  lang: en

## Creator

- name: Hansol Kim
  role: author
- name: Gyusu Lee
  role: author
- name: Jinjae Kim
  role: author
- name: Jiwon Park
  role: author
- name: Andrew S. Kim
  role: author
- name: Jongyun Choi
  role: author
- name: Kenji Watanabe
  role: author
  orcid: https://orcid.org/0000-0003-3701-8119
  organization: National Institute for Materials Science
- name: Takashi Taniguchi
  role: author
  orcid: https://orcid.org/0000-0002-1467-3105
  organization: National Institute for Materials Science
- name: Moon-Ho Jo
  role: author
- name: Hyunyong Choi
  role: author

## Contact agent



## Publisher

organization: American Physical Society (APS)
ror: https://ror.org/

## Managing organization



## Keyword

- subject: Twisted WSe2 homobilayer
  schema: not_defined
- subject: Moiré exciton
  schema: not_defined
- subject: Ultrafast pump-probe spectroscopy
  schema: not_defined

## Rights

- description: "@ American Physical Society"
  identifier: http://rightsstatements.org/vocab/InC/1.0/

## Other identifier(s)



## Data origin

- data_origin_type: other

## Embargo



## Journal

- title: Physical Review B
  issn: 1550235X
  volume: '112'
  issue: '10'
  start_page: 104305
  end_page: 104305
  article_number: '104305'

## Conference



## Related item



## Funding

- identifier: 2019R1A5A1027055
  funder_name: National Research Foundation of Korea
- identifier: IBS-R034-D1
  funder_name: Institute for Basic Science
- funder_name: Guelph Research and Development Centre, Agriculture and Agri-Food Canada
- identifier: RS-2023–00258359
  funder_name: Ministry of Science and ICT, South Korea
- identifier: 2021R1A6C101B418
  funder_name: Ministry of Science and ICT, South Korea
- identifier: 2021R1A2C3005905
  funder_name: National Research Foundation of Korea
- identifier: RS-2024–00413957
  funder_name: National Research Foundation of Korea
- identifier: RS-2024–00466612
  funder_name: National Research Foundation of Korea
- identifier: RS-2024–00487645
  funder_name: National Research Foundation of Korea

## Instrument



## Instrument operator



## Instrument managing organization



## Measurement method



## Specimen



## Chemical composition



## Structure for specimen



## Structural feature for specimen



## Specific property for specimen



## Process for specimen treatment



## Computational method



## Energy level/transition state



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## Fileset

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  filename: 2025A01275G_supplementary materials_r7.docx
  content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
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- id: 574f66e4-49bf-4734-9f9e-de62b8c3c394
  filename: 2025A01275G_manuscript_khs_r7.docx
  content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
  size: 1359273
  md5: e93ffadd15c55500f7b3aa1af58fa458

## Thumbnail

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filename: 2025A01275G_supplementary materials_r7.docx