  Although nanolasers typically have low Q-factors and high lasing thresholds,
they have been successfully implemented with various gain media. Intuitively,
it seems that an increase in the gain coefficient would improve the
characteristics of nanolasers. For a plasmonic nanolaser, in particular, a
distributed-feed-back (DFB) laser, we propose a self-consistent model that
takes into account both spontaneous emission and the multimode character of
laser generation to show that for a given pumping strength, the gain
coefficient has an optimal value at which the radiation intensity is at a
maximum and the radiation linewidth is at a minimum.

Mesoscale and Nanoscale Physics