Lecturer: Dr. Hashem Zoubi Affiliation: Max-Planck Institute for the Physics of Complex Systems Abstract: Since the introduction of the concept of exciton by Ya. I. Frenkel in 1931 and it was successfully applied to explain a wide spectrum of electrical and optical properties in organic and inorganic semiconductors. The recent progress in optical lattice ultracold atoms opened the door to new generation of experiments that suggest new states of matter with completely controllable parameters. We show that optical lattices in the Mott insulator phase considered as artificial crystals can simulate various puzzling effects in solids. We introduce Frenkel like-excitons as coherent states into such a system that can appear via the delocalization of electronic excitations induced by electrostatic interactions. Excitons manifest various unique phenomena, e.g. they allow for quantum engineering of their lifetimes, where bright and dark excitons with superradiant and metastable states are predicted, and which can serve as quantum memory devices. Furthermore, we suggest optical lattices as new active materials for cavity QED. For resonant exciton-photon in the strong coupling regime we introduce cavity polaritons as natural collective eigenstates. These concepts provide a non- destructive observation tool for the system different quantum phases through linear and nonlinear optical processes. We investigated several configurations with different geometry and dimensionality that can realize our results. [1] H. Zoubi, H. Ritsch, Phys. Rev. A 76, 13817 (2007). [2] H. Zoubi, H. Ritsch, New J. Phys. 12, 103014 (2010). [3] H. Zoubi, Europhys. Lett. 100, 24002 (2012). [4] H. Zoubi, H. Ritsch, Adv. At. Mol. Opt. Phys. 62, 171 (2013). [5] H. Zoubi, Phys. Rev. A 89, 043831 (2014). ‏האירוע הזה כולל שיחת וידאו ב-Google Hangouts. הצטרף: https://hangouts.google.com/hangouts/_/mail.huji.ac.il/tba-dr-hashem?hce...