Photoluminescence from plasmon-enhanced single InAs quantum dots

Abstract

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.