Figure 1: Illustration of emission regimes.
From: Giant photon bunching, superradiant pulse emission and excitation trapping in quantum-dot nanolasers
(a) Spontaneous recombination from independent emitters leads to thermal radiation. (b) Using three-dimensional photon confinement in a cavity-quantum electrodynamics laser, spontaneous emission is directed into a single resonator mode. For independent emitters, below threshold the photon emission is uncorrelated, producing thermal or close to thermal light. (c) The exchange of photons introduces correlations between the electronic states of different emitters. A relative phase information ϕ is spontaneously established, and the emission from this entangled many-particle state leads to a superradiant pulse with giant photon bunching. (d) Above threshold, stimulated emission dominates and leads to coherent radiation.
