Correlation effects in the Magnetic properties and nonequilibrium quantum dynamics of spinor Bose Einstein Condensates

Abstract

We explore the changes in the phase diagram of spin-1 Bose gas due to incorporation of correlations and the finite size of the system. We find that the correlations lead to a significant shift in the phase-boundaries referring to second order phase transitions and this effects becomes further amplified when the number of particles decreases. Further, we study the response of various initial conditions corresponding to different phases after a sudden quench in the optical trap frequency in both within and beyond the mean field limit. We find that irrespective of the initial state there is an induced breathing motion of a same frequency which is also equal for all spin states in either limit. Additionally, the incorporation of correlations lead to the formation of filament like structures. Moreover, for the Broken axisymmetry phase, characterized by occupation of all spin states, we even notice spin flip dynamics. To further quantify the effect of correlations we also study the corresponding one-body and two-body correlation function. Finally, we also find that these filaments like structure become more prominent when one decreases the particle number or increases the spin-independent interaction strength of the system.