Dual neutral variables and knot solitons in triplet superconductors

Phys Rev Lett. 2002 Apr 29;88(17):177002. doi: 10.1103/PhysRevLett.88.177002. Epub 2002 Apr 16.


We derive a dual presentation of a free energy functional for spin-triplet superconductors in terms of gauge-invariant variables. The resulting equivalent model in ferromagnetic phase has a form of a version of the Faddeev model. This allows one, in particular, to conclude that spin-triplet superconductors allow formation of stable finite-length closed vortices (knotted solitons).