Semiconducting van der Waals (vdW) systems have recently emerged as a powerful platform for exploring novel effects of light-matter interaction. Amongst the broad suitability of those systems, we highlight two distinct but equally relevant topics for the 2D materials community: the study and manipulation of excitonic properties in twisted Transition metal dichalcogenides (TMDC) multi-layered heterostructures (HS) [1] and the search for high-quality single-photon emitters (SPEs) [2].

This presentation introduces the studies on exciton complexes in twisted vdW heterostructures composed of stacked MoSe₂ and WSe₂ monolayers. Although these structures host spatially indirect interlayer excitons (IX) with unique twist-angle dependent properties, the applications of IXs are limited by their weak oscillator strength, which leads to a significant reduction in emission. To address it, we explore concepts to manipulate and enhance the emission of excitons in twisted TMDC HSs, such as electrostatic doping manipulation, engineering of multi-stacked TMDC layers [3,4,5] and investigate the light-matter coupling of TMDC HSs integrated into multimode dielectric microcavities [6].

Lastly, the prospects and challenges of 2D material-based single-photon emitters will be briefly introduced here. Although this topic has been extensively covered in the literature, we focus on deepening into fabrication improvements to achieve high-quality TMDC single-photon sources. Overall, we address our efforts to investigate the substrate-dependence emission and quantum coherence properties of WSe₂ non-classical light [7,8].

[1] M. Förg et al Nat Commun 12, 1656 (2021).

[2] M. Esmann, S. C. Wein and C. Antón-Solanas Adv. Funct. Mater. 34, 2315936 (2024).

[3] B. Rosa, et al arXiv:2407.08063 (2024).

[4] C. C. Palekar et al 2D Mater. 11 025034 (2024).

[5] C. C. Palekar et al - npj 2D Mater Appl 8, 49 (2024).

[6] C. C. Palekar et al Adv. Mater. 36, 2402624 (2024).

[7] M. von Helversen et al 2D Mater. 10 045034 (2023).

[8] C. S. de Brito et al Nano Letters (2024). DOI: 10.1021/acs.nanolett.4c03686.