Διάλεξη

Παρασκευή 17 Δεκεμβρίου 2010

Ομιλητής

Κωνσταντίνος Γ. Μακρής

Ίδρυμα

Institute for Theoretical Physics, Vienna University of Technology, Austria

Τίτλος

Nonlinear Optics in Lattices

Χώρος

Κτήριο Φυσικού, Βούτες, Αιθ. Σεμιναρίων 3^ου ορόφου

Ώρα

16:00

Γλώσσα

Αγγλικά

Περίληψη

A theoretical investigation of surface lattice solitons in semi-infinite waveguide arrays will be presented. In particular, these nonlinear Tamm states exist at the interface between a periodic and a bulk medium above a specific power threshold, and are the direct outcome of the nonlinearity. Surface solitons were theoretically predicted in various periodic structures of different nonlinear materials, such as AlGaAs (cubic), LiNbO₃ (quadratic) materials. The subsequent experimental observations will also be discussed.

In the second part, the concept of parity-time (PT) symmetry will be introduced in the framework of Optics. This type of symmetry can be realized through a judicious design that involves a combination of optical gain or loss regions. Even though gain and loss are present in this class of non-hermitian potentials, the propagation eigenvalue spectrum is entirely real (bound and radiation modes). The recent experimental realizations of such PT-synthetic materials will also be presented.

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