We predict theoretically and demonstrate experimentally an ellipticity-dependent nonlinear magneto-optic rotation of elliptically polarized light propagating in a medium with atomic coherence. We show that this effect results from hexadecapole and higher-order moments of the atomic coherence, and is associated with an enhancement of Kerr and higher-order nonlinearities accompanied by suppressio...

The capacity region of wavelength division multiplexing in nonlinear fiber optic channels with coherent communication is studied. We show that by optimally using the information from all the channels at the receiver, the loss in the capacity due to the mixing of channels is negligible in the weakly nonlinear regime. On the other hand, with singlechannel detection, capacity saturates as the tota...

Embedding nonlinear media in the slit region of metallic nano-optic lens is proposed as a new method of active modulating the output beam. Two important phenomena, beam deflection and focusing, have been studied in detail. A developed Finite Difference Time Domain (FDTD) method has been performed to account for the nonlinear response. The simulated results show that the deflection angle and foc...

We consider numerical solution of Coupled Nonlinear Schrödinger Equation. We prove stability and convergence in the L2 space for an explicit scheme which estimations is used for implicit scheme and compare both method. As a test we compare numerical solutions of Manakov system with known analytical solitonic solutions and as example of general system evolution of two impulses with different gro...

Self-induced phase modulation in erbium-doped polycrystalline Y(2)O(3) integrated-optic waveguides is studied by use of a Mach-Zehnder interferometric setup. We determined the wavelength dispersion of the nonlinear refractive index near the (4)F(9/2) absorption band and show that it corresponds qualitatively with a Kramers-Krönig analysis. The nonlinear coefficient at 670 nm was determined to b...

We investigate the performance of a combined Tomlinson-Harashima precoding (THP) and a Volterra nonlinear equalization (VNLE) in a nonlinear fiber-optic communication system aiming at a data rate of 100 Gbits/sec. THP-VNLE is compared with a feed-forward VNLE and a combined VNLE decision-feedback equalizer (DFE) by means of performance and computational complexity. Two different transmission sc...

purpose : to report a rare case of large vascularized astrocytoma on optic disc. case report : a 12-year-old boy with history of decreased vision in the left eye since 5-6 months ago was referred to the ocular oncology service at rassoul akram hospital with provisional diagnosis of retinoblastoma. on examination, visual acuity was counting fingers at 50 cm, and a 3+ relative afferent pupillary ...