Researchers from IESL/FORTH, in collaboration with international partners from CEMES, LAAS, INSA, CNRS (France) and Universität Darmstadt (Germany), demonstrate that silicon nanoantennas can dramatically enhance the optical response of atomically thin semiconductors. By coupling monolayer MoS2 to resonant silicon nanostructures, they achieved up to a 30-fold enhancement in second-harmonic generation, together with significant increases in photoluminescence and Raman efficiencies. This study also disentangles the distinct physical origins of enhancement across different optical processes, paving the way for next-generation nanophotonic and quantum technologies.

Summary

The researchers reported that silicon-based dielectric nanoantennas offer an effective platform for engineering light–matter interactions in van der Waals semiconductors. They explained that they had demonstrated near-field coupling between monolayer MoS₂ and silicon nanoantennas arranged in hexagonal lattices with tunable geometric parameters, which led to a threefold enhancement in photoluminescence and an excitation-wavelength-dependent emission aligned with Mie-resonant modes. They added that Raman spectroscopy showed up to an eightfold enhancement in the vibrational modes of MoS₂, while second-harmonic generation exhibited a 20–30-fold increase in efficiency, closely linked to the presence of the nanoantennas. According to them, both experiments and simulations quantified the tunable advantages of the near-field interactions, considering thin-film interference and strain-induced effects. In conclusion, their study highlights the potential of dielectric nanoantennas as a key tool for advancing next-generation nanophotonic technologies.

Reference:

Katrisioti, D., Wiecha, P. R., Cuche, A., Psilodimitrakopoulos, S., Larrieu, G., Müller, J., ... & Paradisanos, I. (2025). Silicon nanoantennas for tailoring the optical properties of MoS2 monolayers, Appl. Phys. Lett., 127(18), 181101. doi: https://doi.org/10.1063/5.0284138