  Photoluminescence (PL) phenomenon from metallic nanostructures has been
explained and understood by several point of views. One of them is based on the
classic harmonic oscillator model, which describes PL of single mode. In this
study, we continue to expand this classic model to a coupling case, which
involves two oscillators that interact with each other together with the
excitation electric field. The new generated modes due to the coupling are
carefully analyzed, including their behaviors varying with the coupling
coefficients in different cases. Furthermore, for practical purpose, PL spectra
and white light scattering spectra of two individual metallic nanostuctures are
calculated as examples employing the model to verify its validity. This work
would give a deeper understanding on coupling PL phenomena and is helpful to
relative applications.
