Origin of the emission within the cavity mode of coupled quantum dot -cavity devices
Although quantum dots (QDs) are usually considered as atomic like emitters, many features of coupled QD-cavity systems cannot simply be described in the Jaynes-Cumming framework. Indeed, it has been widely observed that most of the emission arises from the cavity mode even for large spectral detunings between the QD and the optical mode.
We have investigated the origin of the emission within the cavity mode of deterministically coupled QD-pillar cavities. Time resolved photoluminescence measurements carried out in a wide range of detunings show that the emission within the cavity mode presents the same dynamics as the spectrally closest QD state. When two states of the same QD are equally detuned from the cavity mode, the emission within the mode presents the same decay as the spectrally wider QD state. These observations show that fast dephasing processes of the QD state leads to an efficient emission within the cavity mode. Our results also provide an explanation for recent photon correlation measurements reported on similar systems.
J. Suffczynski et al., Phys. Rev. Lett. 103, 027401 (2009).