We report on a temporal evolution of photoluminescence (PL) spectroscopy ofCuInS$_{2}$/ZnS colloidal quantum dots (QDs) by drop-casting on SiO$_{2}$/Sisubstrates and high quality factor microdisks (MDs) under different atmosphericconditions. Fast PL decay, peak blueshift and linewidth broadening due tophotooxidation have been observed at low excitation power. With furtherincreasing of the excitation power, the PL peak position shows a redshift andlinewidth becomes narrow, which is ascribed to the enhanced F$\ddot{o}$rsterresonant energy transfer between different QDs by photoinduced agglomeration.The oxygen plays an important role in optically induced PL decay which isverified by reduced photobleaching effect in vacuum. When the QDs drop-castedon MDs, photooxidation and photobleaching are accelerated because theexcitation efficiency is greatly enhanced with coupling the pumping laser withthe cavity modes. However, when the emitted photons couple with cavity modes, aPL enhancement by more than 20 times is achieved because of the increasedextraction efficiency and Purcell effects of MDs at room temperature (RT), and35 times at 20 K. The photobleaching can be avoided with a small excitationpower but with a strong PL intensity by taking advantages of high qualityfactor cavities. The high efficient PL emission without photodegradation isvery promising for using CuInS$_{2}$ QDs as high efficient photon emitters atRT, where the photodegradation has always been limiting the practicalapplications of colloidal quantum dots.
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