Inhibition of spontaneous emission in a leaky mode wedge nanocavity

摘要

In this paper, we experimentally investigate the effective role of a wedge-type leaky-mode nanocavity on the inhibition dynamics of the spontaneous emission rate of core-shell CdTe/CdS quantum dots. Three dimensional wedge cavities are fabricated inside a fused silica micro-rod by a conventional fiber-drawing technique, which allow confinement of the quantum dots by the capillary effect. It is demonstrated that both optical and geometrical design of the photonic cavity enforce the generation of leaky modes that cause an inhibition in the spontaneous emission rate monotonically, by about 50%, due to coupling of the emitted photons into continuum modes. Time-resolved experiments confirm that the spontaneous emission rate decreases as the cavity wedge angle increases from 43 to 88 degrees. The physics behind the transduction mechanism of this phenomenon is explained by the weak-coupling regime.