| Quantum dot-microcavity system has extensive application in integrated optical device, such as single quantum dot laser and single photon source. How to handle the interaction between light and matter in this structure is crucial. To address it, one usually has recourse to the master equation technique, which bases on the quantization of light field. The research work within this dissertation uses this technique to investigate the interaction between light and matter in coupled quantum dot-cavity system. Through analyzing structural parameters, single exciton emission and single photon emission is obtained in the quantum dot-cavity system with shallow confinement potential. Lasing properties of a non-resonant quantum dot-cavity system with deep confinement poten-tial is investigated and a low laser threshold is achieved. Moreover, we study the photon transport of quantum dot-cavity system coupled with waveguide.The main research works are as follows:1. Based on the laser model, we investigate the lasing properties of quantum dot-cavity system with shallow confinement potential. The dependence of lasing on cavity decay rate, cavity pump rate and exciton pump rate is amply investigated. The calculation reveals that the whole system achieves lasing easier when the cavity pump rate is smaller. By directly solving the master equation, we derive the spontaneous emission rate, stimulated emission and absorption rate from the density matrix elements. The difference between three different definitions of lasing threshold is investigated by varying coupling rate and cavity decay rate.2. We propose a structure with a quantum dot integrated with coupled photonic res-onators to investigate single photon emission. Due to photon blockade effect be-tween the coupled photonic resonators, single photon emission is generated with second order correlation on the magnitude of10-2. The effect of structural param- eters on single photon emission is studied. It reveals that, the coupled photonic resonators detune with the excitation frequency asymmetrically, second order cor-relation is more close to0. In addition, the calculation reveals that the decay rate of the cavity coupled with quantum dot has a drastic influence on single photon emission.3. Based on the two electrons multi-configuration quantum dot model, we propose a non-resonant quantum dot-cavity model. The detuning between s-exciton and cavity in some way offsets the energy loss caused by the biexciton transition. The influence of detuning on lasing is detailedly investigated. The result reveals that the detuning directly influences the generation of lasing. When the detuning is4.36meV, the laser threshold achieves its optimum Pth=0.197/ps. At this time, the effect of exchange energy is totally offset by the detuning, where the dressed quantum dot is resonant with the cavity. Due to the capture mechanism and the negligible energy space of s and p-exciton, s-exciton pump is introduced. Through comparing the three different excitations, the whole system goes into the lasing and self-quenching regime in advance under s-and p-exciton pump, which fits the experiment better.4. Based on the Input-output theory of coupled cavity-waveguide system, we de-rive the Input-output relation of different structures, such as two quantum dots-cavity system coupled with waveguide. By gradually increased coupling strength, the photon transport is investigated under weak and strong excitation. For weak excitation case, the dips of the transmission appear at the position of√g12+g22which shifts outward with increased coupling rate. At strong excitation, the on-resonance transmissivity is modulated by the quantum dot-cavity coupling rate.5. We derive the Input-output relation of cavities-quantum dot-waveguide system. By means of the Green’s function, the coupling rate between cavity and waveg-uide is analytically defined. With the aid of Heisenberg equation of system op-erators, the analytic transmission is derived under weak excitation limit. The dependence of transmission on the distance and detuning between two cavities is studied. The results reveal that, the transmission is singlet when the left cav-ity resonant with right cavity, and the transmission behaves three-peak structure when the left cavity detuned with right cavity. This method can be applied to treat coupled photonic resonators.Highlights of the dissertation are in the following:1. We establish a laser model for two level quantum dot-cavity system and study the influence of system parameters on lasing. By directly solving the master equa-tion, we relate the spontaneous emission rate, stimulated emission and absorp-tion rate with the density matrix elements. On the basis of dipole approximation and Markov approximation, this derivation doesn’t need addition approximation-s. Through violently solving the master equation, we can get the three emission rates. Using the two level quantum dot-cavity system, we comparing the three definitions of lasing threshold.2. A structure with quantum dot-cavity coupled with another single mode microcav-ity is designed. We systematically investigate the influence of the relative param-eters on the single photon emission. Using the photon blockade effect between two cavities, the system behaves better single photon emission.3. A non-resonant quantum dot-cavity system is established. By compensating for the energy loss of biexciton transition with the detuning between s-exciton and cavity, a lower laser threshold is achieved. Furthermore, s-exciton pump is intro-duced. By investigating the emission properties under different excitation mech-anism, we find that the system goes into lasing and self-quenching regime in ad-vance under s-and p-exciton pump.4. Based on the Input-output theory of coupled cavity-waveguide system, we derive the Input-output relation of different structures, such as two quantum dots-cavity-waveguide system and two cavities-quantum dots-waveguide system. By means of the Green’s function, the coupling rate between cavity and waveguide is an-alytically defined. The photon transport is investigated in detail using different parameters. For the two quantum dots case, the dip of transmission is shifted outward with increased quantum dot-cavity coupling rate at weak excitation, at strong pump the on-resonance transmission is modulated by quantum dot-cavity coupling rate. While for two cavities, the transmission is singlet when the left cav-ity resonant with right cavity, and the transmission behaves three-peak structure when the left cavity detuned with right cavity. |
