Tunable Light-matter Interaction With Quantum Spillover and 2D materials

In this talk I will report our recent efforts on controlling light absorption and emission process through quantum effects in sub-20nm scale coatings. For example, we experimentally demonstrated strong absorption of 20nm thin oxides in the visible spectrum assisted by silver films. We found such a broadband light absorption below the bandgap of the oxide is a manifestation of quantum electron tunneling that penetrate into the thin oxide layer, and it is controlled by the static dielectric constant of the oxide instead of dopant. We also found quantum emitters on a graphene-hBN heterostructure can be switched on and off at mid infrared, by transferring energy into surface phonon polaritons, and this effect can be electrically tuned by biasing the graphene layer. I will also discuss application of these nanostructure for efficient light harvesting and controllable emission, with potential impact in high resolution mid-IR spectroscopy and imaging.