Power-Dependent Luminescence of CdSe/ZnS Nanocrystal Assembled Layer-by-Layer on a Silver Nanorod Array**Supported by the National Natural Science Foundation of China under Grant Nos 11174229, 11374236 and 11204221, and the National Basic Research Program of China under Grant No 2011CB922201.

Abstract

We investigate the power-dependent luminescence of CdSe/ZnS semiconductor quantum dots closely packed layer-by-layer in the proximity of a silver nanorod array cavity. It is found that the emission peak shifts significantly to the longer wavelengths as the excitation power increases, especially when the longitudinal surface plasmon resonance of the Ag nanorod array cavity is adjusted to be close to the emission wavelength. The equivalent gain varies with the coating layer of CdSe/ZnS semiconductor quantum dots and the excitation power is also studied to explain this interesting spectrum-shifting effect. These findings could find applications in the dynamic information processing of active plasmonic and photonic nanodevices.