Optimum gain for plasmonic distributed feedback lasers

TL;DR

This paper presents a self-consistent model for plasmonic DFB nanolasers showing that an optimal gain coefficient maximizes radiation intensity and minimizes linewidth, balancing spontaneous emission and multimode effects.

Contribution

It introduces a novel model that determines the optimal gain coefficient for plasmonic DFB nanolasers considering spontaneous emission and multimode interactions.

Findings

There exists an optimal gain coefficient for maximum radiation intensity.

At this optimal gain, the radiation linewidth is minimized.

The model balances spontaneous emission and multimode effects.

Abstract

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.