Life-time and line-width of individual quantum dots interfaced with graphene

Abstract

We report on the luminescence's life-time and line-width from an array of individual quantum dots; these were interfaced with graphene surface guides or dispersed on a metal film. Our results are consistent with screening by charge carriers. Fluorescence quenching is typically mentioned as a sign that chromophores are interfacing a conductive surface; we found that QD interfaced with conductive layers exhibited shorter life-time and line-broadening but not necessarily fluorescence quenching as the latter may be impacted by molecular concentration, reflectivity and conductor imperfections. We also comment on selective life-time measurements, which, we postulate depend on the specifics of the local density-of-states involved.