等离子体增强InAs单量子点荧光辐射的研究

Photoluminescence from plasmon-enhanced single InAs quantum dots

通过测量光致发光(PL)谱、PL时间分辨光谱及不同激发功率下PL发光强度,研究了低温(5 K)下等离子体对InAs单量子点PL光谱的增强效应.采用电子束蒸发镀膜技术在InAs量子点样品表面淀积了5 nm厚度的金膜,形成纳米金岛膜结构.实验发现,金岛膜有利于量子点样品发光强度的增加,最大PL强度增加了约5倍,其主要物理机理是金岛膜纳米结构提高了量子点PL光谱的收集效率.

Photoluminescences （PLs）, time-resolved PL spectra, and PL intensities each as a function of excitation power from plasmon-enhanced single InAs quantum dots （QDs） are measured for studying the effect of photoluminescence enhancement at a low temperature of 5 K. The 5 nm gold films are deposited on the surface of InAs QD sample by using electron beam evaporation technique, which form nano-gold island membrane structures. It is found that the gold island film is conducive to the enhancement of QD PL intensity and the maximal PL intensity increases up to about 5 times the PL intensity without gold island film. The physical mechanism of the PL increase is that the gold island film nanostructure can improve the QD PL collection efficiency which is very important for realizing the bright single photon sources.