  Optical Mie resonators based on silicon nanostructures allow tuning of
light-matter-interaction with advanced design concepts based on CMOS compatible
nanofabrication. Optically active materials such as transition-metal
dichalcogenide (TMD) monolayers can be placed in the near-field region of such
Mie resonators. Here, we experimentally demonstrate and verify by numerical
simulations coupling between a MoSe2 monolayer and the near-field of dielectric
nanoresonators. Through a comparison of dark-field (DF) scattering spectroscopy
and photoluminescence excitation experiments (PLE), we show that the MoSe2
absorption can be enhanced via the near-field of a nanoresonator. We
demonstrate spectral tuning of the absorption via the geometry of individual
Mie resonators. We show that we indeed access the optical near-field of the
nanoresonators, by measuring a spectral shift between the typical near-field
resonances in PLE compared to the far-field resonances in DF scattering. Our
results prove that using MoSe2 as an active probe allows accessing the optical
near-field above photonic nanostructures, without the requirement of highly
complex near-field microscopy equipment.
