Knotted Solitions in multiband superconductors

[Hornbein]

According to Prof Egor Babaev and others, it seems possible to have knotted solitons in certain superconductors. He has had numerous articles published in Physical Review and Nature. The most understandable one I've found is Hidden symmetry and knot solitons in a charged two-condensate Bose system . If a superconductor has two charge carriers, then electromagnetic interactions between the carriers stabilize the knots. A twisted vortex loop of a preferred size is metastable, as either an increase or decrease in size costs energy. The researchers hope that such solitons can be observed in Type 1.5 superconductors such as magnesium diboride, or in metallic hydrogen in which both the electrons and protons become superconductive. In Type 1.5 superconductors "only one band is superconducting while superfluid density is induced in another band via an interband proximity effect."

In Type 1.5 superconductors the vortices attract at long range and repel at short range, hence they tend to form groups. It would seem that such grouped vortices could form braided knots, but I haven't seen any papers about this.

An even more exotic type of soliton might be found in three band superconductors called a phase soliton which is not a vortex. http://iopscience.iop.org/1367-2630/14/6/063021/article

Finally there is the possibility of a knot soliton made of light. http://physicsworld.com/cws/article/news/2013/oct/16/physicists-tie-light-into-knots A few years ago I saw the abstract of a paper in which it was claimed one of these had been created via a hologram, but I can't be bothered to dig it up.

 

[eljose79]

Hello,

Thank you for bringing this fascinating topic to our attention. The idea of knotted solitons in superconductors is indeed a very interesting and promising area of research. It has been known for some time that superconductors can exhibit various types of vortex structures, and the possibility of knot formation in these structures has been explored in the past.

In the paper you mentioned, Prof Egor Babaev and his team have proposed a novel mechanism for stabilizing knotted solitons in superconductors, based on the electromagnetic interactions between two different types of charge carriers. This is a very intriguing idea, and their theoretical work has been supported by experimental evidence in some superconducting materials.

In particular, the concept of Type 1.5 superconductors, where only one band is superconducting while another band exhibits superfluid density via an interband proximity effect, is a very interesting avenue for exploring the formation of knotted solitons. The fact that these vortices tend to form groups in these materials could indeed lead to the formation of braided knots, as you mentioned.

Furthermore, the possibility of phase solitons in three-band superconductors is also a very exciting prospect. These solitons, which are not vortices, could exhibit even more exotic properties and could potentially be used in various applications.

Finally, the idea of knot solitons made of light is a very intriguing concept. While it may seem far-fetched, there is ongoing research in this area and some promising results have already been obtained. It would be very exciting to see the creation and manipulation of such light-based knot solitons in the future.

Overall, the research on knotted solitons in superconductors is still in its early stages, but the potential for both fundamental understanding and practical applications is immense. We look forward to seeing more developments in this field in the near future. Thank you for sharing this information with us.