Metamaterials based on novel symmetries III
11:15 Invited talk : Wave Mechanics in Media with Local Symmetries: Systematic Pathway to the Breaking of Discrete Symmetries
Peter Schmelcher (1),Christian Morfonios (1),Panagiotis Kalozoumis (2),Fotis Diakonos (2)
(1)University of Hamburg (Germany) , (2)University of Athens (Greece) The concept of local symmetries which hold only in spatially limited domains is developed. This way the parity and Bloch theorems are generalized to the case of broken global symmetry. Local inversion or translation symmetries are shown to yield invariant currents that characterize wave propagation. These currents map the wave field from an arbitrary spatial domain to any symmetry-related domain. Our approach applies to acoustic, optical and matter waves. As examples we provide a classification of perfectly transmitting resonances in completely locally symmetric scattering setups.
11:35 Invited talk : Manipulation of Resonant Modes in a Typical Multi-Mode Laser Cavity by Parity-Time Symmetry
The State University of New York at Buffalo (USA) Effective manipulation of cavity resonant modes is crucial for emission control in laser physics and applications. Using the concept of parity-time symmetry to exploit the interplay between gain and loss, we demonstrate a parity-time symmetry-breaking laser with resonant modes that can be controlled at will. In contrast to conventional ring cavity lasers with multiple competing modes, our parity-time microring laser exhibits intrinsic single-mode with the selective whispering-gallery mode order.
11:55 Invited talk : Bound States in the Continuum in Metamaterials
University of California San Diego (USA) We have recently demonstrated the possibility to construct electromagnetic bound states in the continuum in subwavelength and coupled dielectric particles. This new type of modes, previously conjectured in quantum mechanics have been design, simulated and fabricated. In this talk, I will introduce our approach in constructing BIC and the possibility to realize new photonic devices based on these modes. The current system addresses many challenges in nanophotonics.
12:15 Invited talk : Spontaneous Symmetry Breaking of Scattering Eigenstates in Parity-Time Symmetric Multimode Waveguides
Li Ge (1),Konstantinos G. Makris Makris (2)
(1)The Graduate Center City University of New York (USA) , (2)Vienna University of Technology (Austria) Recently it was predicted that scattering eigenstates of an optical system with Parity-Time (PT) symmetry display a spontaneous symmetry breaking. This was verified in the microwave regime but remains an elusive goal in the optical regime. We propose to observe this phenomenon in a multimode PT-symmetric waveguide, without the need to tune any system parameter.