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Transition metal dichalcogenides (TMDs) are regarded as a possible material platform for quantum information science and related device applications. In TMD monolayers, the dephasing time and inhomogeneity are crucial parameters for any quantum information application. In TMD heterostructures, coupling strength and interlayer exciton lifetimes are also parameters of interest. However, many demonstrations in TMDs can only be realized at specific spots on the sample, presenting a challenge to the scalability of these applications. Here, using multi-dimensional coherent imaging spectroscopy, we shed light on the underlying physics—including dephasing, inhomogeneity, and strain—for a MoSe2 monolayer and identify both promising and unfavorable areas for quantum information applications. We, furthermore, apply the same technique to a MoSe2/WSe2 heterostructure. Despite the notable presence of strain and dielectric environment changes, coherent and incoherent coupling and interlayer exciton lifetimes are mostly robust across the sample. This uniformity is despite a significantly inhomogeneous interlayer exciton photoluminescence distribution that suggests a bad sample for device applications. This robustness strengthens the case for TMDs as a next-generation material platform in quantum information science and beyond. [ABSTRACT FROM AUTHOR]

The unique optical properties of transition metal dichalcogenide (TMD) monolayers have attracted significant attention for both photonics applications and fundamental studies of low-dimensional systems. TMD monolayers of high optical quality, however, have been limited to micron-sized flakes produced by low-throughput and labour-intensive processes, whereas large-area films are often affected by surface defects and large inhomogeneity. Here we report a rapid and reliable method to synthesize macroscopic-scale TMD monolayers of uniform, high optical quality. Using 1-dodecanol encapsulation combined with gold-tape-assisted exfoliation, we obtain monolayers with lateral size > 1 mm, exhibiting exciton energy, linewidth, and quantum yield uniform over the whole area and close to those of high-quality micron-sized flakes. We tentatively associate the role of the two molecular encapsulating layers as isolating the TMD from the substrate and passivating the chalcogen vacancies, respectively. We demonstrate the utility of our encapsulated monolayers by scalable integration with an array of photonic crystal cavities, creating polariton arrays with enhanced light-matter coupling strength. This work provides a pathway to achieving high-quality two-dimensional materials over large areas, enabling research and technology development beyond individual micron-sized devices. The optical quality of large-area transition metal dichalcogenide (TMD) monolayers is usually limited by surface defects and inhomogeneities. Here, the authors report a method based on 1-dodecanol encapsulation to improve the optical properties of TMD monolayers over mm-scale, enabling the fabrication of an array of polariton photonic crystal cavities. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1038/s41467-023-37500-1. Correction to: I Nature Communications i https://doi.org/10.1038/s41467-023-37500-1, published online 01 April 2023 In the "Acknowledgements" section of the original version of this Article, the grant number relating to the Gordon and Betty Moore Foundation was incorrectly given as N031710 and should have been GBMF10694. This has now been corrected in both the PDF and HTML versions of the Article. [Extracted from the article]