Purcell effect of asymmetric dipole source distributions in nanowire resonators

Metal nanowire resonators allow subwavelength mode confinement and thereby the strong Purcell effect. Recent progress in fabrication of plasmonic nanowire lasers requires reliable approaches in studying resonators, where metal nanowire is an essential constitutive element. A semi-analytic study, capable of treating finite-length axially-symmetric nanowire configurations, was reported in. In some nanolaser configurations, however, one needs to treat asymmetric source distributions, e.g. the single quantum dot placed at some distance from the nanowire axis.
We investigate the Purcell effect of the asymmetric source distributions in proximity to the metal nanowire in two configurations: a metal cylinder truncated by the PEC plates and finite metal cylinder in free-space. In order to evaluate Purcell factor the mode eigenvalues are precalculated using Comsol Multiphysics radio frequency module. We compare the eigenfrequency and Purcell factor values calculated in PEC-truncated model against an analytic theory, which accounts for the fundamental surface plasmon - polariton mode in the form of a standing wave between two PEC planes.