Ultrabright photoluminescence spikes and step-wise photoluminescence increase from colloidal silver nanoparticles for patch nanoantennas

Abstract Ultrabright intensity spikes (up to ∼400—900 kcounts/s) appear sporadically in time traces of photoluminescence from 100-nm silver nanocubes used in nanopatch antennas for single-photon source applications. Both 532 and 633 nm laser excitation causes them.