Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Review Article
  • Published:

Excitonic devices with van der Waals heterostructures: valleytronics meets twistronics

Nature Reviews Materials volume 7, pages 449–464 (2022)Cite this article

Subjects

Abstract

2D semiconducting transition metal dichalcogenides comprise an emerging class of materials with distinct properties, including large exciton binding energies that reach hundreds of millielectronvolts and valley-contrasting physics. Thanks to the van der Waals interaction, individual monolayers can be assembled to produce synthetic crystals with tailored properties not found in the constituent materials. The interlayer excitons in these structures provide an optically addressable spin and valley degrees of freedom with long lifetime. These quasi-particles can be controlled in solid-state devices to implement (pseudo)spin-based computation schemes or to study fundamental bosonic interactions. In this Review, we discuss recent progress in the field, focusing on device architectures and engineering techniques that allow the properties of interlayer excitons to be tailored, such as electrostatic modulation, relative twist angle, strain and substrate engineering. Because the excitonic response is highly sensitive to the local environment and layer morphology, we also discuss the advances and challenges in the fabrication of excitonic devices. This examination allows us to highlight critical points that require further investigation, as well as to comment on future research perspectives.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: IXs in van der Waals heterostructures.
Fig. 2: Valley physics of interlayer excitons.
Fig. 3: Recent progress in heterostructure quality and fabrication and characterization methods.
Fig. 4: Control of IXs with electric and magnetic fields.
Fig. 5: Interlayer moiré excitons.
Fig. 6: Substrate engineering of IXs.
Fig. 7: Many-body physics in high-density IX gases.

Similar content being viewed by others

References

  1. Radisavljevic, B., Radenovic, A., Brivio, J., Giacometti, V. & Kis, A. Single-layer MoS2 transistors. Nat. Nanotechnol. 6, 147–150 (2011).

    Article  CAS  Google Scholar 

  2. Wang, Q. H., Kalantar-Zadeh, K., Kis, A., Coleman, J. N. & Strano, M. S. Electronics and optoelectronics of two-dimensional transition metal dichalcogenides. Nat. Nanotechnol. 7, 699–712 (2012).

    Article  CAS  Google Scholar 

  3. Manzeli, S., Ovchinnikov, D., Pasquier, D., Yazyev, O. V. & Kis, A. 2D transition metal dichalcogenides. Nat. Rev. Mater. 2, 1733 (2017).

    Article  CAS  Google Scholar 

  4. Koppens, F. H. L. et al. Photodetectors based on graphene, other two-dimensional materials and hybrid systems. Nat. Nanotechnol. 9, 780–793 (2014).

    Article  CAS  Google Scholar 

  5. Splendiani, A. et al. Emerging photoluminescence in monolayer MoS2. Nano Lett. 10, 1271–1275 (2010).

    Article  CAS  Google Scholar 

  6. Mak, K. F., Lee, C., Hone, J., Shan, J. & Heinz, T. F. Atomically thin MoS2: a new direct-gap semiconductor. Phys. Rev. Lett. 105, 136805 (2010).

    Article  CAS  Google Scholar 

  7. Bertolazzi, S., Brivio, J. & Kis, A. Stretching and breaking of ultrathin MoS2. ACS Nano 5, 9703–9709 (2011).

    Article  CAS  Google Scholar 

  8. Xiao, D., Liu, G.-B., Feng, W., Xu, X. & Yao, W. Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides. Phys. Rev. Lett. 108, 196802 (2012).

    Article  CAS  Google Scholar 

  9. Cao, T. et al. Valley-selective circular dichroism of monolayer molybdenum disulphide. Nat. Commun. 3, 887 (2012).

    Article  CAS  Google Scholar 

  10. Zeng, H., Dai, J., Yao, W., Xiao, D. & Cui, X. Valley polarization in MoS2 monolayers by optical pumping. Nat. Nanotechnol. 7, 490–493 (2012).

    Article  CAS  Google Scholar 

  11. Mak, K. F., He, K., Shan, J. & Heinz, T. F. Control of valley polarization in monolayer MoS2 by optical helicity. Nat. Nanotechnol. 7, 494–498 (2012).

    Article  CAS  Google Scholar 

  12. Koma, A. & Yoshimura, K. Ultrasharp interfaces grown with van der Waals epitaxy. Surf. Sci. 174, 556–560 (1986).

    Article  CAS  Google Scholar 

  13. Geim, A. K. & Grigorieva, I. V. Van der Waals heterostructures. Nature 499, 419–425 (2013).

    Article  CAS  Google Scholar 

  14. Butov, L. V. Excitonic devices. Superlattices Microstruct. 108, 2–26 (2017).

    Article  CAS  Google Scholar 

  15. High, A. A., Hammack, A. T., Butov, L. V., Hanson, M. & Gossard, A. C. Exciton optoelectronic transistor. Opt. Lett. 32, 2466–2468 (2007).

    Article  CAS  Google Scholar 

  16. High, A. A., Novitskaya, E. E., Butov, L. V., Hanson, M. & Gossard, A. C. Control of exciton fluxes in an excitonic integrated circuit. Science 321, 229–231 (2008).

    Article  CAS  Google Scholar 

  17. Grosso, G. et al. Excitonic switches operating at around 100 K. Nat. Photon. 3, 577–580 (2009).

    Article  CAS  Google Scholar 

  18. Pile, D. Excitonics heats up. Nat. Photon. 3, 604–604 (2009).

    Article  CAS  Google Scholar 

  19. Levi, A. F. J. Silicon photonics’ last-meter problem: economics and physics still pose challenges to ‘fiber to the processor’ tech. IEEE Spectr. 55, 38–43 (2018).

    Article  Google Scholar 

  20. Stier, A. V., McCreary, K. M., Jonker, B. T., Kono, J. & Crooker, S. A. Exciton diamagnetic shifts and valley Zeeman effects in monolayer WS2 and MoS2 to 65 Tesla. Nat. Commun. 7, 10643 (2016).

    Article  CAS  Google Scholar 

  21. Gonzalez Marin, J. F., Unuchek, D., Watanabe, K., Taniguchi, T. & Kis, A. MoS2 photodetectors integrated with photonic circuits. npj 2D Mater. Appl. 3, 14 (2019).

    Article  CAS  Google Scholar 

  22. Lee, H. S. et al. Reconfigurable exciton-plasmon interconversion for nanophotonic circuits. Nat. Commun. 7, 13663 (2016).

    Article  CAS  Google Scholar 

  23. Unuchek, D. et al. Room-temperature electrical control of exciton flux in a van der Waals heterostructure. Nature 560, 340–344 (2018).

    Article  CAS  Google Scholar 

  24. Unuchek, D. et al. Valley-polarized exciton currents in a van der Waals heterostructure. Nat. Nanotechnol. 14, 1104–1109 (2019).

    Article  CAS  Google Scholar 

  25. Mueller, T. & Malic, E. Exciton physics and device application of two-dimensional transition metal dichalcogenide semiconductors. npj 2D Mater. Appl. 2, 29 (2018).

    Article  CAS  Google Scholar 

  26. Wang, G. et al. Colloquium: Excitons in atomically thin transition metal dichalcogenides. Rev. Mod. Phys. 90, 021001 (2018).

    Article  CAS  Google Scholar 

  27. Jin, C. et al. Ultrafast dynamics in van der Waals heterostructures. Nat. Nanotechnol. 13, 994–1003 (2018).

    Article  CAS  Google Scholar 

  28. Rivera, P. et al. Interlayer valley excitons in heterobilayers of transition metal dichalcogenides. Nat. Nanotechnol. 13, 1004–1015 (2018).

    Article  CAS  Google Scholar 

  29. Polland, H.-J., Schultheis, L., Kuhl, J., Göbel, E. O. & Tu, C. W. Lifetime enhancement of two-dimensional excitons by the quantum-confined Stark effect. Phys. Rev. Lett. 55, 2610–2613 (1985).

    Article  CAS  Google Scholar 

  30. Charbonneau, S., Thewalt, M. L. W., Koteles, E. S. & Elman, B. Transformation of spatially direct to spatially indirect excitons in coupled double quantum wells. Phys. Rev. B 38, 6287–6290 (1988).

    Article  CAS  Google Scholar 

  31. Haigh, S. J. et al. Cross-sectional imaging of individual layers and buried interfaces of graphene-based heterostructures and superlattices. Nat. Mater. 11, 764–767 (2012).

    Article  CAS  Google Scholar 

  32. Koma, A. Van der Waals epitaxy — a new epitaxial growth method for a highly lattice-mismatched system. Thin Solid Films 216, 72–76 (1992).

    Article  CAS  Google Scholar 

  33. Chernikov, A. et al. Exciton binding energy and nonhydrogenic rydberg series in monolayer WS2. Phys. Rev. Lett. 113, 076802 (2014).

    Article  CAS  Google Scholar 

  34. Chiu, M.-H. et al. Determination of band alignment in the single-layer MoS2/WSe2 heterojunction. Nat. Commun. 6, 7666 (2015).

    Article  CAS  Google Scholar 

  35. Goryca, M. et al. Revealing exciton masses and dielectric properties of monolayer semiconductors with high magnetic fields. Nat. Commun. 10, 4172 (2019).

    Article  CAS  Google Scholar 

  36. Ramasubramaniam, A. Large excitonic effects in monolayers of molybdenum and tungsten dichalcogenides. Phys. Rev. B 86, 115409 (2012).

    Article  CAS  Google Scholar 

  37. Zhang, C. et al. Probing critical point energies of transition metal dichalcogenides: surprising indirect gap of single layer WSe2. Nano Lett. 15, 6494–6500 (2015).

    Article  CAS  Google Scholar 

  38. Özçelik, V. O., Azadani, J. G., Yang, C., Koester, S. J. & Low, T. Band alignment of two-dimensional semiconductors for designing heterostructures with momentum space matching. Phys. Rev. B 94, 035125 (2016).

    Article  CAS  Google Scholar 

  39. Gong, C. et al. Band alignment of two-dimensional transition metal dichalcogenides: application in tunnel field effect transistors. Appl. Phys. Lett. 103, 053513 (2013).

    Article  CAS  Google Scholar 

  40. Kang, J., Tongay, S., Zhou, J., Li, J. & Wu, J. Band offsets and heterostructures of two-dimensional semiconductors. Appl. Phys. Lett. 102, 012111 (2013).

    Article  CAS  Google Scholar 

  41. Kos´mider, K. & Fernández-Rossier, J. Electronic properties of the MoS2–WS2 heterojunction. Phys. Rev. B 87, 075451 (2013).

    Article  CAS  Google Scholar 

  42. Komsa, H.-P. & Krasheninnikov, A. V. Electronic structures and optical properties of realistic transition metal dichalcogenide heterostructures from first principles. Phys. Rev. B 88, 085318 (2013).

    Article  CAS  Google Scholar 

  43. Terrones, H., López-Urías, F. & Terrones, M. Novel hetero-layered materials with tunable direct band gaps by sandwiching different metal disulfides and diselenides. Sci. Rep. 3, 1549 (2013).

    Article  CAS  Google Scholar 

  44. Debbichi, L., Eriksson, O. & Lebègue, S. Electronic structure of two-dimensional transition metal dichalcogenide bilayers from ab initio theory. Phys. Rev. B 89, 205311 (2014).

    Article  CAS  Google Scholar 

  45. Zhang, C. et al. Systematic study of electronic structure and band alignment of monolayer transition metal dichalcogenides in van der Waals heterostructures. 2D Mater. 4, 015026 (2016).

    Article  CAS  Google Scholar 

  46. Ceballos, F., Bellus, M. Z., Chiu, H.-Y. & Zhao, H. Ultrafast charge separation and indirect exciton formation in a MoS2–MoSe2 van der Waals heterostructure. ACS Nano 8, 12717–12724 (2014).

    Article  CAS  Google Scholar 

  47. Hong, X. et al. Ultrafast charge transfer in atomically thin MoS2/WS2 heterostructures. Nat. Nanotechnol. 9, 682–686 (2014).

    Article  CAS  Google Scholar 

  48. Kozawa, D. et al. Evidence for fast interlayer energy transfer in MoSe2/WS2 heterostructures. Nano Lett. 16, 4087–4093 (2016).

    Article  CAS  Google Scholar 

  49. Zhu, H. et al. Interfacial charge transfer circumventing momentum mismatch at two-dimensional van der Waals heterojunctions. Nano Lett. 17, 3591–3598 (2017).

    Article  CAS  Google Scholar 

  50. Nayak, P. K. et al. Probing evolution of twist-angle-dependent interlayer excitons in MoSe2/WSe2 van der Waals heterostructures. ACS Nano 11, 4041–4050 (2017).

    Article  CAS  Google Scholar 

  51. Chen, H. et al. Ultrafast formation of interlayer hot excitons in atomically thin MoS2/WS2 heterostructures. Nat. Commun. 7, 12512 (2016).

    Article  CAS  Google Scholar 

  52. Hill, H. M., Rigosi, A. F., Rim, K. T., Flynn, G. W. & Heinz, T. F. Band alignment in MoS2/WS2 transition metal dichalcogenide heterostructures probed by scanning tunneling microscopy and spectroscopy. Nano Lett. 16, 4831–4837 (2016).

    Article  CAS  Google Scholar 

  53. Wilson, N. R. et al. Determination of band offsets, hybridization, and exciton binding in 2D semiconductor heterostructures. Sci. Adv. 3, e1601832 (2017).

    Article  CAS  Google Scholar 

  54. Chiu, M.-H. et al. Spectroscopic signatures for interlayer coupling in MoS2–WSe2 van der Waals stacking. ACS Nano 8, 9649–9656 (2014).

    Article  CAS  Google Scholar 

  55. Jones, A. M. et al. Spin–layer locking effects in optical orientation of exciton spin in bilayer WSe2. Nat. Phys. 10, 130–134 (2014).

    Article  CAS  Google Scholar 

  56. Wang, Z., Chiu, Y.-H., Honz, K., Mak, K. F. & Shan, J. Electrical tuning of interlayer exciton gases in WSe2 bilayers. Nano Lett. 18, 137–143 (2018).

    Article  CAS  Google Scholar 

  57. Kunstmann, J. et al. Momentum-space indirect interlayer excitons in transition-metal dichalcogenide van der Waals heterostructures. Nat. Phys. 14, 801–805 (2018).

    Article  CAS  Google Scholar 

  58. Karni, O. et al. Infrared interlayer exciton emission in MoS2/WSe2 heterostructures. Phys. Rev. Lett. 123, 247402 (2019).

    Article  CAS  Google Scholar 

  59. Kormányos, A. et al. Monolayer MoS2: trigonal warping, the Gamma valley, and spin-orbit coupling effects. Phys. Rev. B 88, 045416 (2013).

    Article  CAS  Google Scholar 

  60. Kośmider, K., González, J. W. & Fernández-Rossier, J. Large spin splitting in the conduction band of transition metal dichalcogenide monolayers. Phys. Rev. B 88, 245436 (2013).

    Article  CAS  Google Scholar 

  61. Liu, G.-B., Shan, W.-Y., Yao, Y., Yao, W. & Xiao, D. Three-band tight-binding model for monolayers of group-VIB transition metal dichalcogenides. Phys. Rev. B 88, 085433 (2013).

    Article  CAS  Google Scholar 

  62. Xu, X., Yao, W., Xiao, D. & Heinz, T. F. Spin and pseudospins in layered transition metal dichalcogenides. Nat. Phys. 10, 343–350 (2014).

    Article  CAS  Google Scholar 

  63. Rivera, P. et al. Valley-polarized exciton dynamics in a 2D semiconductor heterostructure. Science 351, 688–691 (2016).

    Article  CAS  Google Scholar 

  64. Kim, J. et al. Observation of ultralong valley lifetime in WSe2/MoS2 heterostructures. Sci. Adv. 3, e1700518 (2017).

    Article  CAS  Google Scholar 

  65. Jin, C. et al. Imaging of pure spin-valley diffusion current in WS2–WSe2 heterostructures. Science 360, 893–896 (2018).

    Article  CAS  Google Scholar 

  66. Rhodes, D., Chae, S. H., Ribeiro-Palau, R. & Hone, J. Disorder in van der Waals heterostructures of 2D materials. Nat. Mater. 18, 541–549 (2019).

    Article  CAS  Google Scholar 

  67. Rivera, P. et al. Observation of long-lived interlayer excitons in monolayer MoSe2–WSe2 heterostructures. Nat. Commun. 6, 6242 (2015).

    Article  CAS  Google Scholar 

  68. Ciarrocchi, A. et al. Polarization switching and electrical control of interlayer excitons in two-dimensional van der Waals heterostructures. Nat. Photon. 13, 131–136 (2019).

    Article  CAS  Google Scholar 

  69. Förg, M. et al. Cavity-control of interlayer excitons in van der Waals heterostructures. Nat. Commun. 10, 3697 (2019).

    Article  CAS  Google Scholar 

  70. Jiang, C. et al. Microsecond dark-exciton valley polarization memory in two-dimensional heterostructures. Nat. Commun. 9, 753 (2018).

    Article  CAS  Google Scholar 

  71. Miller, B. et al. Long-lived direct and indirect interlayer excitons in van der Waals heterostructures. Nano Lett. 17, 5229–5237 (2017).

    Article  CAS  Google Scholar 

  72. Nagler, P. et al. Interlayer exciton dynamics in a dichalcogenide monolayer heterostructure. 2D Mater. 4, 025112 (2017).

    Article  CAS  Google Scholar 

  73. Nagler, P. et al. Giant magnetic splitting inducing near-unity valley polarization in van der Waals heterostructures. Nat. Commun. 8, 1551 (2017).

    Article  CAS  Google Scholar 

  74. Jauregui, L. A. et al. Electrical control of interlayer exciton dynamics in atomically thin heterostructures. Science 366, 870–875 (2019).

    Article  CAS  Google Scholar 

  75. Seyler, K. L. et al. Signatures of moiré-trapped valley excitons in MoSe2/WSe2 heterobilayers. Nature 567, 66–70 (2019).

    Article  CAS  Google Scholar 

  76. Srivastava, A. et al. Optically active quantum dots in monolayer WSe2. Nat. Nanotechnol. 10, 491–496 (2015).

    Article  CAS  Google Scholar 

  77. Chakraborty, C., Kinnischtzke, L., Goodfellow, K. M., Beams, R. & Vamivakas, A. N. Voltage-controlled quantum light from an atomically thin semiconductor. Nat. Nanotechnol. 10, 507–511 (2015).

    Article  CAS  Google Scholar 

  78. He, Y.-M. et al. Single quantum emitters in monolayer semiconductors. Nat. Nanotechnol. 10, 497–502 (2015).

    Article  CAS  Google Scholar 

  79. Koperski, M. et al. Single photon emitters in exfoliated WSe2 structures. Nat. Nanotechnol. 10, 503–506 (2015).

    Article  CAS  Google Scholar 

  80. Palummo, M., Bernardi, M. & Grossman, J. C. Exciton radiative lifetimes in two-dimensional transition metal dichalcogenides. Nano Lett. 15, 2794–2800 (2015).

    Article  CAS  Google Scholar 

  81. Robert, C. et al. Exciton radiative lifetime in transition metal dichalcogenide monolayers. Phys. Rev. B 93, 205423 (2016).

    Article  CAS  Google Scholar 

  82. Ross, J. S. et al. Interlayer exciton optoelectronics in a 2D heterostructure p–n junction. Nano Lett. 17, 638–643 (2017).

    Article  CAS  Google Scholar 

  83. Wu, F., Lovorn, T. & MacDonald, A. H. Theory of optical absorption by interlayer excitons in transition metal dichalcogenide heterobilayers. Phys. Rev. B 97, 035306 (2018).

    Article  CAS  Google Scholar 

  84. Yu, H., Wang, Y., Tong, Q., Xu, X. & Yao, W. Anomalous light cones and valley optical selection rules of interlayer excitons in twisted heterobilayers. Phys. Rev. Lett. 115, 187002 (2015).

    Article  CAS  Google Scholar 

  85. Epstein, I. et al. Near-unity light absorption in a monolayer WS2 van der Waals heterostructure cavity. Nano Lett. 20, 3545–3552 (2020).

    Article  CAS  Google Scholar 

  86. Fang, H. H. et al. Control of the exciton radiative lifetime in van der Waals heterostructures. Phys. Rev. Lett. 123, 067401 (2019).

    Article  CAS  Google Scholar 

  87. Mak, K. F. & Shan, J. Photonics and optoelectronics of 2D semiconductor transition metal dichalcogenides. Nat. Photon. 10, 216–226 (2016).

    Article  CAS  Google Scholar 

  88. Lorchat, E. et al. Filtering the photoluminescence spectra of atomically thin semiconductors with graphene. Nat. Nanotechnol. 15, 283–288 (2020).

    Article  CAS  Google Scholar 

  89. Zhang, C. et al. Interlayer couplings, moiré patterns, and 2D electronic superlattices in MoS2/WSe2 hetero-bilayers. Sci. Adv. 3, e1601459 (2017).

    Article  CAS  Google Scholar 

  90. Hsu, W.-T. et al. Negative circular polarization emissions from WSe2/MoSe2 commensurate heterobilayers. Nat. Commun. 9, 1356 (2018).

    Article  CAS  Google Scholar 

  91. Kang, K. et al. High-mobility three-atom-thick semiconducting films with wafer-scale homogeneity. Nature 520, 656–660 (2015).

    Article  CAS  Google Scholar 

  92. Kim, H., Ovchinnikov, D., Deiana, D., Unuchek, D. & Kis, A. Suppressing nucleation in metal–organic chemical vapor deposition of MoS2 monolayers by alkali metal halides. Nano Lett. 8, 5056–5063 (2017).

    Article  CAS  Google Scholar 

  93. Cun, H. et al. Wafer-scale MOCVD growth of monolayer MoS2 on sapphire and SiO2. Nano Res. 12, 2646–2652 (2019).

    Article  CAS  Google Scholar 

  94. Dumcenco, D. et al. Large-area epitaxial monolayer MoS2. ACS Nano 9, 4611–4620 (2015).

    Article  CAS  Google Scholar 

  95. Yu, H. et al. Wafer-scale growth and transfer of highly-oriented monolayer MoS2 continuous films. ACS Nano 11, 12001–12007 (2017).

    Article  CAS  Google Scholar 

  96. Kang, K. et al. Layer-by-layer assembly of two-dimensional materials into wafer-scale heterostructures. Nature 550, 229–233 (2017).

    Article  CAS  Google Scholar 

  97. Liao, M. et al. Precise control of the interlayer twist angle in large scale MoS2 homostructures. Nat. Commun. 11, 2153 (2020).

    Article  CAS  Google Scholar 

  98. Hong, J. et al. Exploring atomic defects in molybdenum disulphide monolayers. Nat. Commun. 6, 6293 (2015).

    Article  CAS  Google Scholar 

  99. Cevallos, F. A. et al. Liquid salt transport growth of single crystals of the layered dichalcogenides MoS2 and WS2. Cryst. Growth Des. 19, 5762–5767 (2019).

    Article  CAS  Google Scholar 

  100. Dean, C. R. et al. Boron nitride substrates for high-quality graphene electronics. Nat. Nanotechnol. 5, 722–726 (2010).

    Article  CAS  Google Scholar 

  101. Mayorov, A. S. et al. Micrometer-scale ballistic transport in encapsulated graphene at room temperature. Nano Lett. 11, 2396–2399 (2011).

    Article  CAS  Google Scholar 

  102. Wang, L. et al. One-dimensional electrical contact to a two-dimensional material. Science 342, 614–617 (2013).

    Article  CAS  Google Scholar 

  103. Kretinin, A. V. et al. Electronic properties of graphene encapsulated with different two-dimensional atomic crystals. Nano Lett. 14, 3270–3276 (2014).

    Article  CAS  Google Scholar 

  104. Alexeev, E. M. et al. Imaging of interlayer coupling in van der Waals heterostructures using a bright-field optical microscope. Nano Lett. 17, 5342–5349 (2017).

    Article  CAS  Google Scholar 

  105. Lui, C. H. et al. Observation of interlayer phonon modes in van der Waals heterostructures. Phys. Rev. B 91, 165403 (2015).

    Article  CAS  Google Scholar 

  106. Desai, S. B. et al. Gold-mediated exfoliation of ultralarge optoelectronically-perfect monolayers. Adv. Mater. 28, 4053–4058 (2016).

    Article  CAS  Google Scholar 

  107. Shim, J. et al. Controlled crack propagation for atomic precision handling of wafer-scale two-dimensional materials. Science 362, 665–670 (2018).

    Article  CAS  Google Scholar 

  108. Liu, F. et al. Disassembling 2D van der Waals crystals into macroscopic monolayers and reassembling into artificial lattices. Science 367, 903–906 (2020).

    Article  CAS  Google Scholar 

  109. Cao, Y. et al. Superlattice-induced insulating states and valley-protected orbits in twisted bilayer graphene. Phys. Rev. Lett. 117, 116804 (2016).

    Article  CAS  Google Scholar 

  110. Kim, K. et al. van der Waals heterostructures with high accuracy rotational alignment. Nano Lett. 16, 1989–1995 (2016).

    Article  CAS  Google Scholar 

  111. Cao, Y. et al. Correlated insulator behaviour at half-filling in magic-angle graphene superlattices. Nature 556, 80–84 (2018).

    Article  CAS  Google Scholar 

  112. Cao, Y. et al. Unconventional superconductivity in magic-angle graphene superlattices. Nature 556, 43–50 (2018).

    Article  CAS  Google Scholar 

  113. Malard, L. M., Alencar, T. V., Barboza, A. P. M., Mak, K. F. & de Paula, A. M. Observation of intense second harmonic generation from MoS2 atomic crystals. Phys. Rev. B 87, 201401 (2013).

    Article  CAS  Google Scholar 

  114. Kumar, N. et al. Second harmonic microscopy of monolayer MoS2. Phys. Rev. B 87, 161403 (2013).

    Article  CAS  Google Scholar 

  115. Tran, K. et al. Evidence for moiré excitons in van der Waals heterostructures. Nature 567, 71–75 (2019).

    Article  CAS  Google Scholar 

  116. Schaibley, J. R. et al. Directional interlayer spin-valley transfer in two-dimensional heterostructures. Nat. Commun. 7, 13747 (2016).

    Article  CAS  Google Scholar 

  117. Rosenberger, M. R. et al. Twist angle dependent atomic reconstruction and moiré patterns in transition metal dichalcogenide heterostructures. ACS Nano 14, 4550–4558 (2020).

    Article  CAS  Google Scholar 

  118. Yankowitz, M. et al. Emergence of superlattice Dirac points in graphene on hexagonal boron nitride. Nat. Phys. 8, 382–386 (2012).

    Article  CAS  Google Scholar 

  119. Hunt, B. et al. Massive Dirac fermions and Hofstadter butterfly in a van der Waals heterostructure. Science 340, 1427–1430 (2013).

    Article  CAS  Google Scholar 

  120. Yoo, H. et al. Atomic and electronic reconstruction at the van der Waals interface in twisted bilayer graphene. Nat. Mater. 18, 448–453 (2019).

    Article  CAS  Google Scholar 

  121. Sung, J. et al. Broken mirror symmetry in excitonic response of reconstructed domains in twisted MoSe2/MoSe2 bilayers. Nat. Nanotechnol. 15, 750–754 (2020).

    Article  CAS  Google Scholar 

  122. McGilly, L. J., Kerelsky, A., Finney, N. R. et al. Visualization of moiré superlattices. Nat. Nanotechnol. 15, 580–584 (2020).

    Article  CAS  Google Scholar 

  123. Sushko, A. et al. High resolution imaging of reconstructed domains and moire patterns in functional van der Waals heterostructure devices. Preprint at https://arxiv.org/abs/1912.07446 (2019).

  124. Fang, H. et al. Strong interlayer coupling in van der Waals heterostructures built from single-layer chalcogenides. Proc. Natl Acad. Sci. USA 111, 6198–6202 (2014).

    Article  CAS  Google Scholar 

  125. Zhang, L. et al. Highly valley-polarized singlet and triplet interlayer excitons in van der Waals heterostructure. Phys. Rev. B 100, 041402 (2019).

    Article  CAS  Google Scholar 

  126. Wang, G. et al. Polarization and time-resolved photoluminescence spectroscopy of excitons in MoSe2 monolayers. Appl. Phys. Lett. 106, 112101 (2015).

    Article  CAS  Google Scholar 

  127. Jin, C. et al. Identification of spin, valley and moiré quasi-angular momentum of interlayer excitons. Nat. Phys. 15, 1140–1144 (2019).

    Article  CAS  Google Scholar 

  128. Wang, Z. et al. Evidence of high-temperature exciton condensation in two-dimensional atomic double layers. Nature 574, 76–80 (2019).

    Article  CAS  Google Scholar 

  129. Ivanov, A. L. Quantum diffusion of dipole-oriented indirect excitons in coupled quantum wells. Europhys. Lett. 59, 586 (2002).

    Article  CAS  Google Scholar 

  130. Fogler, M. M., Butov, L. V. & Novoselov, K. S. High-temperature superfluidity with indirect excitons in van der Waals heterostructures. Nat. Commun. 5, 4555 (2014).

    Article  CAS  Google Scholar 

  131. Scuri, G. et al. Electrically tunable valley dynamics in twisted WSe2/WSe2 bilayers. Phys. Rev. Lett. 124, 217403 (2020).

    Article  CAS  Google Scholar 

  132. Raja, A. et al. Dielectric disorder in two-dimensional materials. Nat. Nanotechnol. 14, 832–837 (2019).

    Article  CAS  Google Scholar 

  133. Yuan, L. et al. Twist-angle-dependent interlayer exciton diffusion in WS2–WSe2 heterobilayers. Nat. Mater. 19, 617–623 (2020).

    Article  CAS  Google Scholar 

  134. Sanvitto, D. et al. Observation of charge transport by negatively charged excitons. Science 294, 837–839 (2001).

    Article  CAS  Google Scholar 

  135. Brotons-Gisbert, M. et al. Spin–layer locking of interlayer excitons trapped in moiré potentials. Nat. Mater. 19, 630–636 (2020).

    Article  CAS  Google Scholar 

  136. Ubrig, N. et al. Design of van der Waals interfaces for broad-spectrum optoelectronics. Nat. Mater. 19, 299–304 (2020).

    Article  CAS  Google Scholar 

  137. Yu, H., Liu, G.-B., Tang, J., Xu, X. & Yao, W. Moiré excitons: from programmable quantum emitter arrays to spin-orbit–coupled artificial lattices. Sci. Adv. 3, e1701696 (2017).

    Article  CAS  Google Scholar 

  138. Yu, H., Liu, G.-B. & Yao, W. Brightened spin-triplet interlayer excitons and optical selection rules in van der Waals heterobilayers. 2D Mater. 5, 035021 (2018).

    Article  CAS  Google Scholar 

  139. Baek, H. et al. Highly energy-tunable quantum light from moiré-trapped excitons. Sci. Adv. 6, eaba8526 (2020).

    Article  CAS  Google Scholar 

  140. Jin, C. et al. Observation of moiré excitons in WSe2/WS2 heterostructure superlattices. Nature 567, 76–80 (2019).

    Article  CAS  Google Scholar 

  141. Alexeev, E. M. et al. Resonantly hybridized excitons in moiré superlattices in van der Waals heterostructures. Nature 567, 81–86 (2019).

    Article  CAS  Google Scholar 

  142. Wang, J. et al. Diffusivity reveals three distinct phases of interlayer excitons in MoSe2/WSe2 heterobilayers. Phys. Rev. Lett. 126, 106804 (2021).

    Article  CAS  Google Scholar 

  143. Li, Z. et al. Interlayer Exciton Transport in MoSe2/WSe2 heterostructures. ACS Nano 15, 1539–1547 (2021).

    Article  CAS  Google Scholar 

  144. Kulig, M. et al. Exciton diffusion and halo effects in monolayer semiconductors. Phys. Rev. Lett. 120, 207401 (2018).

    Article  CAS  Google Scholar 

  145. Sun, Z. et al. Excitonic transport driven by repulsive dipolar interaction in a van der Waals heterostructure. Nat. Photon. 16, 79–85 (2022).

    Article  CAS  Google Scholar 

  146. Choi, J. et al. Moiré potential impedes interlayer exciton diffusion in van der Waals heterostructures. Sci. Adv. 6, eaba8866 (2020).

    Article  CAS  Google Scholar 

  147. Tartakovskii, A. Moiré or not. Nat. Mater. 19, 581–582 (2020).

    Article  CAS  Google Scholar 

  148. Cadiz, F. et al. Exciton diffusion in WSe2 monolayers embedded in a van der Waals heterostructure. Appl. Phys. Lett. 112, 152106 (2018).

    Article  CAS  Google Scholar 

  149. Perea-Causín, R. et al. Exciton propagation and halo formation in two-dimensional materials. Nano Lett. 19, 7317–7323 (2019).

    Article  CAS  Google Scholar 

  150. Darlington, T. P. et al. Imaging strain-localized excitons in nanoscale bubbles of monolayer WSe2 at room temperature. Nat. Nanotechnol. 15, 854–860 (2020).

    Article  CAS  Google Scholar 

  151. Moon, H. et al. Dynamic exciton funneling by local strain control in a monolayer semiconductor. Nano Lett. 20, 6791–6797 (2020).

    Article  CAS  Google Scholar 

  152. He, Y. et al. Strain-induced electronic structure changes in stacked van der Waals heterostructures. Nano Lett. 16, 3314–3320 (2016).

    Article  CAS  Google Scholar 

  153. Kremser, M. et al. Discrete interactions between a few interlayer excitons trapped at a MoSe2–WSe2 heterointerface. npj 2D Mater. Appl. 4, 8 (2020).

    Article  CAS  Google Scholar 

  154. Bai, Y. et al. Excitons in strain-induced one-dimensional moiré potentials at transition metal dichalcogenide heterojunctions. Nat. Mater. 19, 1068–1073 (2020).

    Article  CAS  Google Scholar 

  155. Alexeev, E. M. et al. Emergence of highly linearly polarized interlayer exciton emission in MoSe2/WSe2 heterobilayers with transfer-induced layer corrugation. ACS Nano 14, 11110–11119 (2020).

    Article  CAS  Google Scholar 

  156. Raja, A. et al. Coulomb engineering of the bandgap and excitons in two-dimensional materials. Nat. Commun. 8, 15251 (2017).

    Article  Google Scholar 

  157. Dufferwiel, S. et al. Exciton–polaritons in van der Waals heterostructures embedded in tunable microcavities. Nat. Commun. 6, 8579 (2015).

    Article  CAS  Google Scholar 

  158. Rivera, P. et al. Coupling of photonic crystal cavity and interlayer exciton in heterobilayer of transition metal dichalcogenides. 2D Mater. 7, 015027 (2019).

    Article  CAS  Google Scholar 

  159. Pozo-Zamudio, O. D. et al. Electrically pumped WSe2-based light-emitting van der Waals heterostructures embedded in monolithic dielectric microcavities. 2D Mater. 7, 031006 (2020).

    Article  CAS  Google Scholar 

  160. Paik, E. Y. et al. Interlayer exciton laser of extended spatial coherence in atomically thin heterostructures. Nature 576, 80–84 (2019).

    Article  CAS  Google Scholar 

  161. Liu, Y. et al. Room temperature nanocavity laser with interlayer excitons in 2D heterostructures. Sci. Adv. 5, eaav4506 (2019).

    Article  CAS  Google Scholar 

  162. Schneider, C., Glazov, M. M., Korn, T., Höfling, S. & Urbaszek, B. Two-dimensional semiconductors in the regime of strong light–matter coupling. Nat. Commun. 9, 2695 (2018).

    Article  CAS  Google Scholar 

  163. Bimberg, D. et al. InGaAs–GaAs quantum-dot lasers. IEEE J. Sel. Top. Quantum Electron. 3, 196–205 (1997).

    Article  CAS  Google Scholar 

  164. Sortino, L. et al. Enhanced light–matter interaction in an atomically thin semiconductor coupled with dielectric nano-antennas. Nat. Commun. 10, 5119 (2019).

    Article  CAS  Google Scholar 

  165. Wang, Z. et al. Giant photoluminescence enhancement in tungsten-diselenide–gold plasmonic hybrid structures. Nat. Commun. 7, 11283 (2016).

    Article  CAS  Google Scholar 

  166. Kern, J. et al. Nanoantenna-enhanced light–matter interaction in atomically thin WS2. ACS Photon. 2, 1260–1265 (2015).

    Article  CAS  Google Scholar 

  167. Eisenstein, J. P. & MacDonald, A. H. Bose–Einstein condensation of excitons in bilayer electron systems. Nature 432, 691–694 (2004).

    Article  CAS  Google Scholar 

  168. Burg, G. W. et al. Strongly enhanced tunneling at total charge neutrality in double-bilayer graphene-WSe2 heterostructures. Phys. Rev. Lett. 120, 177702 (2018).

    Article  CAS  Google Scholar 

  169. Butov, L. V., Lai, C. W., Ivanov, A. L., Gossard, A. C. & Chemla, D. S. Towards Bose–Einstein condensation of excitons in potential traps. Nature 417, 47–52 (2002).

    Article  CAS  Google Scholar 

  170. Sigl, L. et al. Signatures of a degenerate many-body state of interlayer excitons in a van der Waals heterostack. Phys. Rev. Res. 2, 042044 (2020).

    Article  CAS  Google Scholar 

  171. Conti, S., Van der Donck, M., Perali, A., Peeters, F. M. & Neilson, D. Doping-dependent switch from one- to two-component superfluidity in coupled electron–hole van der Waals heterostructures. Phys. Rev. B 101, 220504 (2020).

    Article  CAS  Google Scholar 

  172. Weston, A. et al. Atomic reconstruction in twisted bilayers of transition metal dichalcogenides. Nat. Nanotechnol. 15, 592–597 (2020).

    Article  CAS  Google Scholar 

  173. Regan, E. C. et al. Mott and generalized Wigner crystal states in WSe2/WS2 moiré superlattices. Nature 579, 359–363 (2020).

    Article  CAS  Google Scholar 

  174. Tang, Y. et al. Simulation of Hubbard model physics in WSe2/WS2 moiré superlattices. Nature 579, 353–358 (2020).

    Article  CAS  Google Scholar 

  175. Shimazaki, Y. et al. Strongly correlated electrons and hybrid excitons in a moiré heterostructure. Nature 580, 472–477 (2020).

    Article  CAS  Google Scholar 

  176. Wang, L. et al. Correlated electronic phases in twisted bilayer transition metal dichalcogenides. Nat. Mater. 19, 861–866 (2020).

    Article  CAS  Google Scholar 

  177. Forsythe, C. et al. Band structure engineering of 2D materials using patterned dielectric superlattices. Nat. Nanotechnol. 13, 566–571 (2018).

    Article  CAS  Google Scholar 

  178. Kasprzak, J. et al. Bose–Einstein condensation of exciton polaritons. Nature 443, 409–414 (2006).

    Article  CAS  Google Scholar 

  179. Marzin, J.-Y., Gérard, J.-M., Izraël, A., Barrier, D. & Bastard, G. Photoluminescence of single InAs quantum dots obtained by self-organized growth on GaAs. Phys. Rev. Lett. 73, 716–719 (1994).

    Article  CAS  Google Scholar 

  180. Shoujun, Z. et al. Giant enhancement of cathodoluminescence of monolayer transitional metal dichalcogenides semiconductors. Nano Lett. 17, 6475–6480 (2017).

    Article  CAS  Google Scholar 

  181. Bragança, H., Zeng, H., Dias, A. C., Correa, J. H. & Qu, F. Magnetic-gateable valley exciton emission. npj Comput. Mater. 6, 90 (2020).

    Article  CAS  Google Scholar 

  182. Gong, Y. et al. Vertical and in-plane heterostructures from WS2/MoS2 monolayers. Nat. Mater. 13, 1135–1142 (2014).

    Article  CAS  Google Scholar 

  183. Kim, K. et al. Controlled moiré bands in twisted bilayer graphene. Proc. Natl Acad. Sci. USA 114, 3364–3369 (2017).

    Article  CAS  Google Scholar 

  184. Halbertal, D. et al. Moiré metrology of energy landscapes in van der Waals heterostructures. Nat. Commun. 12, 242 (2021).

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Institute of Electrical and Microengineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland

    Alberto Ciarrocchi, Fedele Tagarelli, Ahmet Avsar & Andras Kis

  2. Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland

    Alberto Ciarrocchi, Fedele Tagarelli, Ahmet Avsar & Andras Kis

  3. School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne, UK

    Ahmet Avsar

Authors
  1. Alberto Ciarrocchi
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Fedele Tagarelli
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Ahmet Avsar
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Andras Kis
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

The authors contributed equally to all aspects of the article.

Corresponding author

Correspondence to Andras Kis.

Ethics declarations

Competing interests

The authors declare no competing interests.

Peer review

Peer review information

Nature Reviews Materials thanks You Zhou and the other, anonymous, reviewers for their contribution to the peer review of this work.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Ciarrocchi, A., Tagarelli, F., Avsar, A. et al. Excitonic devices with van der Waals heterostructures: valleytronics meets twistronics. Nat Rev Mater 7, 449–464 (2022). https://doi.org/10.1038/s41578-021-00408-7

Download citation

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41578-021-00408-7

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing