Παρασκευή και χαρακτηρισμός δισδιάστατων κρυστάλλων περοβσκίτη αλογονιδίου προς πολαριτονικές εφαρμογές

The main aim of this work was to fabricate high quality thin 2D Halide perovskite crystals and use them to demonstrate strong light-matter coupling in various device geometries. We explored two alternative methods to fabricate crystals, namely, liquid exfoliation and solution method. We characterized the material structure using XRD as well as microscope/SEM techniques and employ optical measurements such as PL, Reflectivity, Power and Temperature dependence, to characterize exciton emission properties in this material. Liquid exfoliation method produced relatively small sized perovskite crystals not compatible with their introduction inside wavelength sized cavity. The second method, provided us with the much better results both in crystal size and structure as well as excitonic emission. Τhe successfully optimized material was then incorporated inside optical cavity and on top of a Bragg reflector. Large angle white light reflectivity measurements at room temperature revealed the appearance of resonant mode residing at the surface of the Bragg mirror whose coupling with overlaying perovskite excitons was studied. Finally, strong-light matter coupling at room temperature was obtained when incorporating such crystals inside DBR mirror-based cavities demonstrating the great promise these materials pose for real world polaritonic applications