Phase Separation In Spin-orbit-angular-momentum Coupling Bose-einstein Condensate Systems

Since the experimental realization of the Bose-Einstein Condensate(BEC)in 1995,due to its high controllability,BEC has become an ideal medium for scientists to expect to understand quantum systems.In the fields of atomic physics and materials science,spin orbit coupling(SOC)has been a hot research object.In the field of materials or cold atoms,previous theories about spin-orbit coupling have been developed around spin and momentum,such as Rashba coupling,Dresselhaus coupling,and Weyl coupling.In November and December 2018,the experimental group led by Taiwanese scholar Lin Yu ru and others experimentally realized the coupling of cold atom spin and orbital angular momentum: the angular momentum of particles was transferred to the particle centroid by laser and coupled with the particle’s spin.This is physically closer to our traditional theoretical framework of atomic physics.Because of this important achievement,we have further promoted our attention and research enthusiasm for spin-orbit coupling BEC.This article is based on this hot experiment.This paper mainly conducts two aspects of research,one is the theoretical simulation of the spin orbit angular momentum coupling experiment.On the basis of the SAOMC single particle Hamiltonian given in the literature,the 1-d coupled and 3-d coupled GP equations satisfied by the multi-body system are obtained by means of the average field theory and the variational principle.The numerical method is used: Crank-Nicolson method and Fourier pseudo-spectral method is used to numerically simulate the BEC density distribution,condensed matter density distribution,resulting in a single direction coupling experiment results very well,on this basis,made a 3 d coupled to promote,by adjusting the macro adjustable parameters to find the dynamic properties of condensed matter,SOAM coupling leads to the spin distinguish the phase separation of the location of rich structure,phase separation and its degree.In addition,ring phase,vortex lattice phase and various types of immiscible phase are all found in our simulation,which makes us have a deeper understanding of spin-orbit coupling BEC and has certain reference value for subsequent experiments...