Since discrete multilevel transitions of quantum-dot molecules driven by external electromagnetic fields can exhibit quantum coherence effects, such an optical characteristic can be utilized to control propagation of ...Since discrete multilevel transitions of quantum-dot molecules driven by external electromagnetic fields can exhibit quantum coherence effects, such an optical characteristic can be utilized to control propagation of electromagnetic wave through a quantum-dot molecule dielectric film. Since inner-dot tunneling in quantum-dot molecules can be controlled by a gate voltage, destructive quantum coherence among multilevel transitions in quantum-dot molecule would give rise to EIT (electromagnetically induced transparency). In this report, we shall investigate controllable on- and off-resonance tunneling effects of an incident electromagnetic wave through such a quan-tum-dot-molecule dielectric film, of which the optical response is tuned by the switchable gate voltage. We have found from the theoretical mechanism that a high gate voltage can cause the EIT phenomenon of quan-tum-dot-molecule systems, and under the condition of on-resonance light tunneling through the thin film, the probe field will propagation without loss if the probe frequency detuning is zero. By taking advantage of these effects sensitive to the tunable gate voltage, such quantum coherence would be inte-grated in certain photonic structures, and some devices such as photonic switching and transistors can be designed. Transient evolution of optical characteristics in the quantum-dot-molecule dielectric film (once the tunable gate voltage is turned on or off) is also considered in this report.展开更多
A hybrid plasmonic waveguide containing silicon core, silver cap and ultra-thin sandwiched SiO2 layer is studied. By analyzing the mode distribution patterns and the curves of mode effective index, we show how the pla...A hybrid plasmonic waveguide containing silicon core, silver cap and ultra-thin sandwiched SiO2 layer is studied. By analyzing the mode distribution patterns and the curves of mode effective index, we show how the plasmonic mode around the metal surface is coupled with the fundamental mode in the silicon core to form a squeezed hybrid mode. The ability of the hybrid plasmonic waveguide in energy confinement is also discussed quantitatively.展开更多
文摘Since discrete multilevel transitions of quantum-dot molecules driven by external electromagnetic fields can exhibit quantum coherence effects, such an optical characteristic can be utilized to control propagation of electromagnetic wave through a quantum-dot molecule dielectric film. Since inner-dot tunneling in quantum-dot molecules can be controlled by a gate voltage, destructive quantum coherence among multilevel transitions in quantum-dot molecule would give rise to EIT (electromagnetically induced transparency). In this report, we shall investigate controllable on- and off-resonance tunneling effects of an incident electromagnetic wave through such a quan-tum-dot-molecule dielectric film, of which the optical response is tuned by the switchable gate voltage. We have found from the theoretical mechanism that a high gate voltage can cause the EIT phenomenon of quan-tum-dot-molecule systems, and under the condition of on-resonance light tunneling through the thin film, the probe field will propagation without loss if the probe frequency detuning is zero. By taking advantage of these effects sensitive to the tunable gate voltage, such quantum coherence would be inte-grated in certain photonic structures, and some devices such as photonic switching and transistors can be designed. Transient evolution of optical characteristics in the quantum-dot-molecule dielectric film (once the tunable gate voltage is turned on or off) is also considered in this report.
基金Acknowledgements This work was supported partially by the National Natural Science Foundation of China （Grant Nos. 61178062 and 61108022）.
文摘A hybrid plasmonic waveguide containing silicon core, silver cap and ultra-thin sandwiched SiO2 layer is studied. By analyzing the mode distribution patterns and the curves of mode effective index, we show how the plasmonic mode around the metal surface is coupled with the fundamental mode in the silicon core to form a squeezed hybrid mode. The ability of the hybrid plasmonic waveguide in energy confinement is also discussed quantitatively.
