Spontaneous spatial order in two-dimensional ferromagnetic spin-orbit coupled uniform spin-1 condensate solitons

We demonstrate spontaneous spatial order in stripe and super-lattice solitons in a Rashba spin-orbit (SO) coupled spin-1 uniform quasi-two-dimensional (quasi-2D) ferromagnetic Bose-Einstein condensate (BEC). For weak SO coupling, the solitons are of the (-1, 0, +1) or (0, +1, +2) type with intrinsic vorticity, where the numbers in the parentheses denote angular momentum in spin components F-z = +1,0, -1, respectively. For intermediate SO coupling, three types of solitons are found: (a) circularly-asymmetric solitons, (b) circularly-symmetric (-1, 0, +1)- and (c) (0, +1, +2)-type multi-ring solitons maintaining the above-mentioned vortices in respective components. For large SO coupling, quasi-degenerate stripe and super-lattice solitons are found in addition to the circularly-asymmetric solitons. A super-lattice soliton forms a 2D square lattice structure in the total density as in a super-solid; in component densities it may have either (i) a 1D stripe pattern or (ii) a 2D square lattice structure. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

In this study, spontaneous spatial order in stripe and super-lattice solitons in a Rashba spin-orbit coupled spin-1 ferromagnetic Bose-Einstein condensate is demonstrated. The type of solitons changes with the strength of the SO coupling, with different types of solitons found for weak, intermediate, and large SO coupling strengths.