Exciton-polarons in the presence of strongly correlated electronic states in a MoSe2/WSe2 moiré superlattice

Aidan J. Campbell; Mauro Brotons-Gisbert; Hyeonjun Baek; Valerio Vitale; Takashi Taniguchi; Kenji Watanabe; Johannes Lischner; Brian D. Gerardot

doi:10.1038/s41699-022-00358-w

Exciton-polarons in the presence of strongly correlated electronic states in a MoSe₂/WSe₂ moiré superlattice

Aidan J. Campbell, Mauro Brotons-Gisbert, Hyeonjun Baek, Valerio Vitale, Takashi Taniguchi, Kenji Watanabe, Johannes Lischner, Brian D. Gerardot^*

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

26 Citations (Scopus)

91 Downloads (Pure)

Abstract

Two-dimensional moiré materials provide a highly tunable platform to investigate strongly correlated electronic states. Such emergent many-body phenomena can be optically probed in moiré systems created by stacking two layers of transition metal dichalcogenide semiconductors: optically injected excitons can interact with itinerant carriers occupying narrow moiré bands to form exciton-polarons sensitive to strong correlations. Here, we investigate the behaviour of excitons dressed by a Fermi sea localised by the moiré superlattice of a molybdenum diselenide (MoSe₂)/tungsten diselenide (WSe₂) twisted hetero-bilayer. At a multitude of fractional fillings of the moiré lattice, we observe ordering of both electrons and holes into stable correlated electronic states. Magneto-optical measurements reveal extraordinary Zeeman splittings of the exciton-polarons due to exchange interactions in the correlated hole phases, with a maximum close to the correlated state at one hole per site. The temperature dependence of the Zeeman splitting reveals antiferromagnetic ordering of the correlated holes across a wide range of fractional fillings. Our results illustrate the nature of exciton-polarons in the presence of strongly correlated electronic states and reveal the rich potential of the MoSe₂/WSe₂ platform for investigations of Fermi–Hubbard and Bose–Hubbard physics.

Original language	English
Article number	79
Journal	npj 2D Materials and Applications
Volume	6
DOIs	https://doi.org/10.1038/s41699-022-00358-w
Publication status	Published - 4 Nov 2022

ASJC Scopus subject areas

General Chemistry
General Materials Science
Condensed Matter Physics
Mechanics of Materials
Mechanical Engineering

Access to Document

10.1038/s41699-022-00358-wLicence: CC BY

Download pdf
© The Author(s) 2022.
Final published version, 1.71 MBLicence: CC BY

Cite this

@article{ee67186d4bde42a1bdf3d2b0219cb94c,

title = "Exciton-polarons in the presence of strongly correlated electronic states in a MoSe2/WSe2 moir{\'e} superlattice",

abstract = "Two-dimensional moir{\'e} materials provide a highly tunable platform to investigate strongly correlated electronic states. Such emergent many-body phenomena can be optically probed in moir{\'e} systems created by stacking two layers of transition metal dichalcogenide semiconductors: optically injected excitons can interact with itinerant carriers occupying narrow moir{\'e} bands to form exciton-polarons sensitive to strong correlations. Here, we investigate the behaviour of excitons dressed by a Fermi sea localised by the moir{\'e} superlattice of a molybdenum diselenide (MoSe2)/tungsten diselenide (WSe2) twisted hetero-bilayer. At a multitude of fractional fillings of the moir{\'e} lattice, we observe ordering of both electrons and holes into stable correlated electronic states. Magneto-optical measurements reveal extraordinary Zeeman splittings of the exciton-polarons due to exchange interactions in the correlated hole phases, with a maximum close to the correlated state at one hole per site. The temperature dependence of the Zeeman splitting reveals antiferromagnetic ordering of the correlated holes across a wide range of fractional fillings. Our results illustrate the nature of exciton-polarons in the presence of strongly correlated electronic states and reveal the rich potential of the MoSe2/WSe2 platform for investigations of Fermi–Hubbard and Bose–Hubbard physics.",

author = "Campbell, {Aidan J.} and Mauro Brotons-Gisbert and Hyeonjun Baek and Valerio Vitale and Takashi Taniguchi and Kenji Watanabe and Johannes Lischner and Gerardot, {Brian D.}",

note = "Funding Information: We thank Mikhail M. Glazov for fruitful discussions. This work was supported by the EPSRC (grant nos. EP/P029892/1 and EP/L015110/1), the ERC (grant no. 725920) and the EU Horizon 2020 research and innovation program (grant agreement no. 820423). M.B.-G. is supported by a Royal Society University Research Fellowship. B.D.G. is supported by a Wolfson Merit Award from the Royal Society and a Chair in Emerging Technology from the Royal Academy of Engineering. V.V. and J.L. acknowledge funding from the EPSRC (grant no. EP/S025324/1). K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan (Grant Number JPMXP0112101001) and JSPS KAKENHI (Grant Numbers 19H05790, 20H00354 and 21H05233). Publisher Copyright: {\textcopyright} 2022, The Author(s).",

year = "2022",

month = nov,

day = "4",

doi = "10.1038/s41699-022-00358-w",

language = "English",

volume = "6",

journal = "npj 2D Materials and Applications",

issn = "2397-7132",

publisher = "Nature Publishing Group",

}

TY - JOUR

T1 - Exciton-polarons in the presence of strongly correlated electronic states in a MoSe2/WSe2 moiré superlattice

AU - Campbell, Aidan J.

AU - Brotons-Gisbert, Mauro

AU - Baek, Hyeonjun

AU - Vitale, Valerio

AU - Taniguchi, Takashi

AU - Watanabe, Kenji

AU - Lischner, Johannes

AU - Gerardot, Brian D.

N1 - Funding Information: We thank Mikhail M. Glazov for fruitful discussions. This work was supported by the EPSRC (grant nos. EP/P029892/1 and EP/L015110/1), the ERC (grant no. 725920) and the EU Horizon 2020 research and innovation program (grant agreement no. 820423). M.B.-G. is supported by a Royal Society University Research Fellowship. B.D.G. is supported by a Wolfson Merit Award from the Royal Society and a Chair in Emerging Technology from the Royal Academy of Engineering. V.V. and J.L. acknowledge funding from the EPSRC (grant no. EP/S025324/1). K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan (Grant Number JPMXP0112101001) and JSPS KAKENHI (Grant Numbers 19H05790, 20H00354 and 21H05233). Publisher Copyright: © 2022, The Author(s).

PY - 2022/11/4

Y1 - 2022/11/4

N2 - Two-dimensional moiré materials provide a highly tunable platform to investigate strongly correlated electronic states. Such emergent many-body phenomena can be optically probed in moiré systems created by stacking two layers of transition metal dichalcogenide semiconductors: optically injected excitons can interact with itinerant carriers occupying narrow moiré bands to form exciton-polarons sensitive to strong correlations. Here, we investigate the behaviour of excitons dressed by a Fermi sea localised by the moiré superlattice of a molybdenum diselenide (MoSe2)/tungsten diselenide (WSe2) twisted hetero-bilayer. At a multitude of fractional fillings of the moiré lattice, we observe ordering of both electrons and holes into stable correlated electronic states. Magneto-optical measurements reveal extraordinary Zeeman splittings of the exciton-polarons due to exchange interactions in the correlated hole phases, with a maximum close to the correlated state at one hole per site. The temperature dependence of the Zeeman splitting reveals antiferromagnetic ordering of the correlated holes across a wide range of fractional fillings. Our results illustrate the nature of exciton-polarons in the presence of strongly correlated electronic states and reveal the rich potential of the MoSe2/WSe2 platform for investigations of Fermi–Hubbard and Bose–Hubbard physics.

AB - Two-dimensional moiré materials provide a highly tunable platform to investigate strongly correlated electronic states. Such emergent many-body phenomena can be optically probed in moiré systems created by stacking two layers of transition metal dichalcogenide semiconductors: optically injected excitons can interact with itinerant carriers occupying narrow moiré bands to form exciton-polarons sensitive to strong correlations. Here, we investigate the behaviour of excitons dressed by a Fermi sea localised by the moiré superlattice of a molybdenum diselenide (MoSe2)/tungsten diselenide (WSe2) twisted hetero-bilayer. At a multitude of fractional fillings of the moiré lattice, we observe ordering of both electrons and holes into stable correlated electronic states. Magneto-optical measurements reveal extraordinary Zeeman splittings of the exciton-polarons due to exchange interactions in the correlated hole phases, with a maximum close to the correlated state at one hole per site. The temperature dependence of the Zeeman splitting reveals antiferromagnetic ordering of the correlated holes across a wide range of fractional fillings. Our results illustrate the nature of exciton-polarons in the presence of strongly correlated electronic states and reveal the rich potential of the MoSe2/WSe2 platform for investigations of Fermi–Hubbard and Bose–Hubbard physics.

UR - http://www.scopus.com/inward/record.url?scp=85141355892&partnerID=8YFLogxK

U2 - 10.1038/s41699-022-00358-w

DO - 10.1038/s41699-022-00358-w

M3 - Article

AN - SCOPUS:85141355892

SN - 2397-7132

VL - 6

JO - npj 2D Materials and Applications

JF - npj 2D Materials and Applications

M1 - 79

ER -

Exciton-polarons in the presence of strongly correlated electronic states in a MoSe₂/WSe₂ moiré superlattice

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this