Influence of the phonon-mediated coupling on the properties of a single quantum-dot laser
Jia‐pei Zhu, Hui Huang, Gao‐xiang Li
We theoretically investigate the influence of the phonon-mediated coupling on the properties of the laser generated by a single red-detuned quantum dot (QD), where the QD is coherently driven and coupled to a microscopic cavity which can be engineered in a photonic band-gap (PBG) material. In the low-temperature limit, the phonon-mediated coupling is deleterious to the emission of photon into cavity field and the threshold behavior of the laser persists after the inclusion of the phonon-mediated processes. Without being engineered in the PBG material, if the damping rate $\ensuremath{\kappa}$ of the cavity is close to but smaller than the phonon-mediated spontaneous emission rate $\ensuremath{\gamma}$ of the dot, the photon statistics of the cavity field change from super-Poissonian to sub-Poissonian. The nonclassical effect can be achieved due to the phonon-mediated processes induced by the electron-phonon interaction and the off-resonant dot-cavity coupling. The nonclassical effect can be enhanced by the PBG material. When the effect of the thermal phonon is taken into account, the cavity field exhibits the super-Poissonian property. If $\ensuremath{\kappa}$ is much smaller than $\ensuremath{\gamma}$, the phonon-mediated processes can lead to the increase (decrease) of the photons provided that the incoherent pumping rate is lower (higher) than the effective phonon-mediated threshold. But, if $\ensuremath{\kappa}$ is close to or larger than $\ensuremath{\gamma}$, the emission of the photon may dominate the absorption process, strengthening the intensity of the cavity field.
Physical Review A•Aug 19, 2013•3 citations