• dot
• microcavity

In the last few years optical microcavities have become increasingly important for the
study of the light-matter interactions. Among materials that can be used as active medium in microcavities, particular interest has been attracted by semiconductor Colloidal Quantum Dots (CQDs). This experimental thesis aims to the fabrication and optical characterization of hybrid organic-inorganic microcavities, consisting of two planar mirrors and an active layer made of CdSe/ZnS CQDs dispersed in a polystyrene (PS) host matrix. The first phase of the work was focused on the dispersion of CQDs in solution and the formation of thin films of CQDs in PS through spin coating. The transmission and photoluminescence (PL) spectra were measured by varying the temperature of the samples from room temperature down to 4 K. PL quantum yield (PLQY) measurements were also performed.
The second phase of the experimental work was devoted to the fabrication of high reflectivity mirrors. Thin films of Ag and distributed Bragg reflectors (DBRs) were deposited on quartz substrates by using thermal and electron-beam evaporation processes, respectively. Afterwards, different microcavities were fabricated analyzing the optical properties with different quality factors. The first sample was a reference cavity, made of a film of bare PS sandwiched between two Ag mirrors. The second set of samples was made of film of CQDs in PS sandwiched between a DBR and an Ag film. In the third set of microcavity samples, two DBR mirrors were used as bottom and top mirrors with an active medium made by film of CQDs in PS.
Finally, the optical properties of the microcavities were studied through angle-resolved
transmission and PL measurements.