Hot Electron Generation and Manipulation in Nano-spiked Plasmonic Cavity Arrays

The generation of the localized surface plasmon resonance (LSPR) on the surface of plasmonic structures in the nanoscale has paved the way for advanced biosensing, surpassing the conventional detection limits. The electric field enhancement (electromagnetic hot spots) between two plasmonic nano structures at close quarters produces hot electrons with a change in the electron density of the material. Techniques such as photoinjection are suitable to inject hot electrons from the metal crossing the Schottky barrier to the semiconductor leading to the development of photocurrent. sea urchin looking spiked nanoparticles serve a great interest in research of plasmonic materials as they can generate hot electrons at higher rate compared to other structures. By means of finite element method (FEM) analysis, we investigate the electric field enhancement generated between the cavity of nano star spike pairs and extend the study to an array of them. We further do a parametric study and identify the importance of using such an array to generate hot electrons whose applications are envisaged for light harvesting, enhanced photodetection, photo catalysis etc.