Improved antibunching by using high-excitation pulses from a single semiconductor quantum dot—a theoretical study

Abstract

We study the intensity dependence of single-photon emission from a single semiconductor quantum dot after pulsed excitation. A semiconductor model is introduced that accounts for various configurations resulting from the occupation of the localized single-particle states with carriers. A detailed account is given on how the photon correlation dynamics and the antibunching can be calculated. We predict a novel effect, where, for strong excitation, the formation of multiexciton configurations during the excitation pulse leads to an improved antibunching signature in g 2 .

Hybrid quantum-classical modeling of quantum dot devices

“…in Ref. [65]. However, in electrically driven devices, the carrier densities, the electric field and the current densities, which usually drive the transition rates, strongly depend on the applied voltage and can vary over many orders of magnitude.…”

“…Due to cavity effects, the decay rate is slightly modified with respect to the free space decay rate, which is accounted for by the Purcell factors P i,f . The Weisskopf-Wigner rate is applicable in low Q optical resonators, where the photonic density of states varies insignificantly over the linewidth of the emitter [15,65]. Using the parameters given in Appendix F, all decay rates are found to be approximately 10 9 s −1 .…”

“…Ref. [65]. For the bright exciton line, we identify the photon creation operator with the projector a † = |0 X i | (with i = 1 or 2) and use the quantum regression theorem [28] to evaluate Eq.…”

“…For many applications, the generation of single photons at certain instances of time is required. Electrically driven QD-based single-photon sources offer an easy off-resonant excitation scheme [4,65], where the QD is excited by short voltage pulses. This process shall be simulated in the following, where we apply rectangular voltage pulses with a fixed duration of 100 ps superimposed on a DC bias of 1.35 V as illustrated in Fig.…”