Optical Solitons

Optical solitons are remarkable entities in the world of light. They are beams or pulses of light that maintain their shape as they travel through certain nonlinear materials. This unique behavior is the result of a delicate balance between diffraction/dispersion, which tend to spread the light, and the focusing effect of the nonlinear material.  

The concept of solitons dates back to 1834, when John Scott Russell observed a solitary wave propagating unchanged in the Union Canal in Scotland. Since then, solitons have become a cornerstone in various fields, including optics, fluid mechanics, cosmology, particle physics, biology, and condensed matter physics. 

One of the most fascinating aspects of solitons is their ability to retain their shape and exhibit particle-like behavior during collisions (see the video). This has led to numerous applications, such as: supercontinuum generation, optical switching, highly accurate optical clocks, microwave oscillators, to mention a few.

Although various soliton solutions are known, it is rare to find stable fundamental bright solitons with complex amplitude structures and at the same time with the uniform phase. 

We discovered that the interplay between nonlocal nonlinear light–matter attraction and repulsion can lead to novel types of solutions so-called Tower and Volcano Solitons in two spatial dimensions and double and multi-peak solitons in one dimensional space. We find unusual new fundamental soliton solutions exhibiting complex intensity but constant phase profiles with rectangular and cylindrical symmetries. We also employ an analytically tractable novel model for a complex linear potential whose two-peak ground states mimic two-peak solitons. 

Relevant publications: