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Exciton condensate in van der Waals layered materials

Nature Reviews Physics volume 7, pages 388–401 (2025)Cite this article

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Abstract

Van der Waals layered materials have emerged as a platform for exploring exciton condensation, a phenomenon that reflects quantum coherence and collective behaviour. Unlike traditional quantum Hall systems, 2D layered materials offer a unique opportunity to observe exciton condensation without external magnetic field and at relatively high temperatures, making them highly attractive for both fundamental studies and potential applications. This Perspective focuses on recent advances in understanding the electrical transport behaviours of exciton condensates in 2D layered materials and the strategies proposed to achieve high-temperature exciton condensation, while addressing the challenges and discussing potential future developments in this area.

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Fig. 1: Exciton condensate in double-bilayer graphene.
Fig. 2: Exciton condensation in the absence of magnetic field.
Fig. 3: Excitonic insulators in MoSe2–h-BN–WSe2 heterostructures.
Fig. 4: Exciton condensation using moiré superlattices.

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Acknowledgements

This work was supported by the National Research Foundation of Korea (NRF) grants, funded by the Korean Government (MSIT) (NRF-RS202400450540), the Institute for Basic Science (IBS-R036-D1), and the Hubei University of Technology, China.

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Authors and Affiliations

  1. Department of Physics, Incheon National University, Incheon, Republic of Korea

    Byoung Hee Moon

  2. Center for Low-Dimensional Quantum Materials, Hubei University of Technology, Wuhan, China

    Ashok Mondal & Young Hee Lee

  3. Center for Integrated Nanostructure Physics, Sungkyunkwan University, Suwon, Republic of Korea

    Ashok Mondal & Young Hee Lee

  4. The School of Physics and Astronomy, Monash University, Melbourne, Victoria, Australia

    Dmitry K. Efimkin

  5. Center for 2D Quantum Heterostructures, Institute for Basic Science (IBS), Suwon, Republic of Korea

    Young Hee Lee

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Moon, B.H., Mondal, A., Efimkin, D.K. et al. Exciton condensate in van der Waals layered materials. Nat Rev Phys 7, 388–401 (2025). https://doi.org/10.1038/s42254-025-00834-4

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