Aug 1 2019
Light can never propagate endlessly without any dissipation in nearly all media, even in a vacuum. Light pulses called solitons travel along fibers for long distances without any change in shape or losing focus, and have found applications in data transmission.
However, the solitons slowly dissipate if the medium through which they propagate does not have ultra-low absorbance.
From the 1980s, Nikolay Rosanov from the National Research University of Information Technologies, Mechanics, and Optics (ITMO), St. Petersburg, Russia and his colleagues have been striving to come up with a solution to this challenge—laser solitons. Currently, a colloquium paper describing their recent research in this area has been published in EPJ D.
Rosanov and his team started their study with computer simulations, indicating that it was theoretically feasible to create a stable soliton in a wide-aperture laser by stabilizing it using external radiation. Soon, this prediction was experimentally validated, and the team has analyzed these so-called dissipative solitons from then.
Most recently, the scientists have theoretically shown that it is feasible to develop such solitons without using stable and coherent external radiation. They used parallel programming on high-performance supercomputers to first model a light pulse localized in one dimension (a 1D soliton) before using their method to model solitons in two and subsequently three dimensions.
The internal structure of the 3D solitons is intricate with unique topologies. Descriptive names such as “apple,” “Solomon knot,” and “trefoil” have been given to these topologies and they have been demonstrated to merge.
Rosanov and his team still have questions to answer before their theory can be practically applied. However, once it is put into practice, the stability of these solitons and of their topology points toward prospective applications in digital information storage. There is a high possibility of using computers with laser soliton arrays in the place of existing hard disks someday.
Rosanov and his team recognize financial support from the Russian Science Foundation for their study.