Centro Grandi Strumenti d'Ateneo, Università di Cagliari, Monserrato (CA), Italy.
Nanotechnology. 2012 Jan 13;23(1):015201. doi: 10.1088/0957-4484/23/1/015201.
CdSe/CdS colloidal nanocrystals are members of a novel class of light-emitting nanoparticles with remarkable optical properties such as suppressed fluorescence blinking and enhanced emission from multiexciton states. These properties have been linked to the suppression of non-radiative Auger recombination. In this work we employ ultrafast spectroscopy techniques to identify optical signatures of neutral and charged excitonic and multiexcitonic states. We show that Auger recombination of biexcitons is not suppressed, while we observe optical gain and amplified spontaneous emission from multiexciton states and from long-lived charged-exciton states.
硒化镉/硫化镉胶体纳米晶体是一类新型的发光纳米粒子，具有显著的光学性质，如抑制荧光闪烁和增强多激子态的发射。这些性质与非辐射俄歇复合的抑制有关。在这项工作中，我们采用超快光谱技术来识别中性和带电激子和多激子态的光学特征。我们表明，双激子的俄歇复合并没有被抑制，而我们观察到多激子态和长寿命带电激子态的光增益和受激辐射。
