Fundamental Formulation for Plasmonic Nanolasers

We develop a fundamental formulation of plasmonic nanolasers from Fermi´s Golden rule, taking into account the inhomogeneity and dispersion of the cavity media. We demonstrate that the electromagnetic energy confinement factor and the corresponding effective volume lead to a more consistent formulation for the rate equations of nanolasers. We also use a Fabry-Perot nanolaser based on the plasmonic slab waveguide as an example and compare the energy confinement factor with other counterparts. In particular, we show that the power confinement factor is inappropriate for plasmonic cavity modes.