Investigation of Electromagnetic Hotspots in Metal Infiltrated Metalattices Using Electron Energy Loss Spectroscopy (EELS)*

Metalattices are 3D periodic, ordered and interconnected nanostructures with periodicity size range between 1 nm – 100 nm. Tuning the functional properties of metalattice can happen by infiltrating them with semiconductor materials (like Si, Ge etc) and/or metals (Ag, Pt, Pd, Ni etc). In this research, monochromated Scanning Transmission Electron Microscopy (STEM) and Electron Energy Loss Spectroscopy (EELS) are shown as promising techniques in characterizing both the spatial and spectral properties enabling direct mapping of electromagnetic hotspots associated with the localized surface plasmon resonances at the nanoscale which can give us a depth understanding of plasmonic behavior in infiltrated nano-opals. Of particular interest are metal filled nano-opals that exhibit dark plasmon modes resulting from vanishing dipole moments that can lead to storing electromagnetic energy more efficiently and making them as future candidates for various applications such as enhanced biological and chemical sensors.