Gap Solitons in Assymmetric Dual-Core Nonlinear Optical Fibers
Abstract
A new nonlinear optical medium which can support gap solitons is proposed, an asymmetric dual core fiber with opposite signs of the dispersion in its two cores, which can be easily fabricated choosing the carrier wavelength close to the zero-dispersion point. We consider soliton solutions, combining the analysis of the dispersion relation for the linearized system, the variational approximation for the full nonlinear one, and direct numerical methods. We find that in the case when the cores are asymmetric but still have the same sign of the dispersion, the general picture of the solutions is qualitatively the same as studied recently in the model with identical dispersions in the two cores, the asymmetry being solely accounted for by a phase velocity mismatch between the cores. The case when the dispersion is zero in one core is special: in this case, the system's spectrum simultaneously has one semi-infinite and one finite gaps. In the most interesting case when the dispersion in one core is normal (and the system has only a finite gap in its spectrum), we find novel features of the gap soliton: its tails may be decaying with oscillations (which opens way to nontrivial bound states of the solitons), the energy in the soliton's normal core component may be, quite counterintuitively, equal to or larger than the energy in the anomalous core, and a part of the gap where the solitons might exist remains empty, containing no actual soliton solutions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1997
- Accession Number
- ADA342070
Entities
People
- B. A. Malomed
- D. J. Kaup
Organizations
- Clarkson University