Size and dimension effect on volume plasmon energy of nanomaterials

The influence of size and dimension on the volume plasmon energy of nanomaterials is examined, and the effect of band-gap variation and lattice contraction is explicitly included in our improvised phenomenological model. The advantage of this improvised model is the ability to predict the volume plasmon energy for low dimensional materials, literally free from any arbitrarily adjustable parameters. We find that the volume plasmon energy increases almost exponentially with decreasing size and this increase is shown to be the most evident for nanoparticles, as compared to nanowires and nanofilms of the same material. This is largely due to the variation in the surface/volume ratio with dimension modulation. More importantly, our improvised model outperforms other reported ones, bringing our predicted results closest to available experiments. In particular, for semiconducting/semi-metal nanoarchitectures, we demonstrate that the rapid increase in volume plasmon energy of nanomaterials is a direct consequence and interplay of band-gap variation and lattice contraction.