2, University of Arkansas, Fayetteville, Arkansas, United States
3, University of Geneva, Geneva, , Switzerland
5, National Renewable Energy Laboratory, Golden, Colorado, United States
4, University of Savoy Mont Blanc, Annecy, , France
6, Ruprecht-Karls University Heidelberg, Heidelberg, , Germany
Two-dimensional (2D) transition metal dichalcogenides (TMD) functionalized with plasmonic metal nanoantennas (NA) exhibit rich energy conversion capabilities as a material platform for optoelectronics and sustainable energy. This work examined (i) plasmon-enhanced nonlinear second harmonic generation (SHG) and (ii) injection of plasmonic hot electrons into 2D TMD via coordinated multi-photon microscopy, hyper Rayleigh Scattering (HRS), electron energy-loss spectroscopy (EELS), and discrete dipole computation. Augmented local fields by NA surface plasmon resonance enhanced SHG from monolayer MoS2 at efficiencies of up to 0.025 %/W. Hyper Rayleigh scattering (HRS) assessed the second-order nonlinear susceptibility for WS2 monolayers to be 250±12 pm/V. Quantum yield of plasmonic hot electrons transported to 2D TMD was measured locally for two NA-TMD hybrids by EELS, revealing dependence on bonding characteristics at the metal-TMD junction. Highest measured efficiency was 11±5% for NA physicochemically bonded to WS2 edge disulfides via redox-directed self-assembly.