Spin correlation and discrete symmetry in spinor Bose-Einstein condensates.
We study spin correlations in Bose-Einstein condensates of spin 1 bosons with scatterings dominated by a total spin equal 2 channel. We show that the low energy spin dynamics in the system can be mapped into an o(n) nonlinear sigma model. n = 3 at the zero magnetic field limit and n = 2 in the presence of weak magnetic fields. In an ordered phase, the ground state has a discrete Z2 symmetry and is degenerate under the group [U(1)xS(n-1)]/Z(2). We explore consequences of the discrete symmetry and propose some measurements to probe it.
Zhou
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Physics Department, Princeton University, Princeton, New Jersey 08544, USA.