| The realization of Bose-Einstein condensates(BEC)provides a good platform for studying various forms of topological excitations and novel quantum phase transitions.In particular,the realization of synthetic spin-orbit coupling has greatly enriched the study of cold-atom systems,and exploring the new novel topology in spin-orbit coupled BEC has become a hot topic in cold-atom physics and other atomic crossover fields.It has been found that spin-orbit coupling cannot only stabilize various topological excitation but also produce novel quantum phases.NIST and Rashba spin-orbit coupling have been widely studied.A variety of gauge field models have been proposed,although many models have not been realized due to the experimental conditions,they are still the driving force of theoretical and experimental workers’ research.Inspired by these findings,this paper investigates two-dimensional topological excitations coupled to other forms of spin vector and linear momentum in two-component BEC and one-dimensional soliton excitation coupled to the SU(3)spin-orbit coupling in spin-1 BEC.They reveal that different kinds of coupling forms will produce different novel topological excitation,and expounds the physical mechanism behind different topological excitation.Our work is divided into the following two parts(1)One-dimensional topological excitations in SU(3)spin-orbit coupling modelThe spin-1 BEC Gross-Pitaevskii equation with SU(3)spin-orbit coupling term is solved by numerical simulation.Compared with the numerical results with the conventional SU(2)spin-orbit coupling,we find that a novel soliton excitation can be obtained in this novel SU(3)spin-orbit coupled condensates.We investigate in detail the nature of this novel soliton excitation and the physical mechanism of its generation.These findings contribute to the exploration of novel solitons in quantum systems(2)2D topological excitation of other forms of spin vector and linear momentum couplingTwo-dimensional topological excitation of spin-orbit coupling(pxσz+pyσy)of other forms of spin vector and linear momentum in two-component BEC is studied by numerical simulation.It is found that the system shows novel two-dimensional vortex pair excitation(meron-pair),which is different from the previous theoretical work of two-dimensional Rashba-type spin-orbit coupling.Two vortex pairs are connected by domain wall and show different topologies and spin textures.we conduct a detailed topology classification,reveal the physical mechanism behind it,and discuss the effect of Rabi coupling,which provides a feasible experimental scheme for people to realize this kind of topological structure. |
