Dynamical Properties of Nanolasers Based on Few Discrete Emitters

We investigate the dynamical properties of nanolasers comprising a few two-level emitters coupled to an optical cavity. A set of rate equations is derived, and is shown to agree very well with a solution of the full master equation model. Using a linearized version of these rate equations, we can analytically express the response of the nanolaser to a modulation of the pumping rate. These results are compared with the modulation response obtained directly from the master equation using a novel method. We show that contrary to conventional semiconductor lasers, the nanolaser is typically over-damped and displays a dip in the modulation bandwidth as the two-level systems become inverted. Both these features can be traced back to the use of discrete emitters that are incoherently pumped.