Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Physical Sciences and Mathematics
Unidirectional Nonlinear Pt-Symmetric Optical Structures, Hamidreza Ramezani, Tsampikos Kottos, Ramy El-Ganainy, Demetrios N. Christodoulides
Unidirectional Nonlinear Pt-Symmetric Optical Structures, Hamidreza Ramezani, Tsampikos Kottos, Ramy El-Ganainy, Demetrios N. Christodoulides
Ramy El-Ganainy
We show that nonlinear optical structures involving a balanced gain-loss profile can act as unidirectional optical valves. This is made possible by exploiting the interplay between the fundamental symmetries of parity (P) and time (T), with optical nonlinear effects. This unidirectional dynamics is specifically demonstrated for the case of an integrable PT -symmetric nonlinear system.
Pt-Symmetric Optical Lattices, Konstantinos G. Makris, Ramy El-Ganainy, Demetrios N. Christodoulides, Z. H. Musslimani
Pt-Symmetric Optical Lattices, Konstantinos G. Makris, Ramy El-Ganainy, Demetrios N. Christodoulides, Z. H. Musslimani
Ramy El-Ganainy
The basic properties of Floquet-Bloch (FB) modes in parity-time (PT )-symmetric optical lattices are examined in detail. Due to the parity-time symmetry of such complex periodic potentials, the corresponding FB modes are skewed (nonorthogonal) and nonreciprocal. The conjugate pairs of these FB modes are obtained by reflecting both the spatial coordinate and the Bloch momentum number itself. The orthogonality conditions are analytically derived for a single cell, for both a finite and an infinite lattice. Some of the peculiarities associated with the diffraction dynamics in PT lattices such as nonreciprocity, power oscillations, and phase dislocations, are also examined.
Light-Induced Self-Synchronizing Flow Patterns, Elad Greenfield, Carmel Rotschild, Alexander Szameit, Jonathan Nemirovsky, Ramy El-Ganainy, Demetrios N. Christodoulides, Meirav Saraf, Efrat Lifshitz, Mordechai Segev
Light-Induced Self-Synchronizing Flow Patterns, Elad Greenfield, Carmel Rotschild, Alexander Szameit, Jonathan Nemirovsky, Ramy El-Ganainy, Demetrios N. Christodoulides, Meirav Saraf, Efrat Lifshitz, Mordechai Segev
Ramy El-Ganainy
In this paper, we present the observation of light-induced self-synchronizing flow patterns in a light–fluid system. A light beam induces local flow patterns in a fluid, which oscillate periodically or chaotically in time. The oscillations within different regions of the fluid interact with each other through heat- and surface-tension-induced fluid waves, and they become synchronized. We demonstrate optical control over the state of synchronization and over the temporal correlation between different parts of the flow field. Finally, we provide a model to elucidate these results and we suggest further ideas on light controlling flow and vice versa.