Quantum Phase Transition in an Antiferromagnetic Spinor Bose-Einstein Condensate
Quantum Phase Transition in an Antiferromagnetic Spinor Bose-Einstein Condensate
We have experimentally observed the dynamics of an antiferromagnetic sodium Bose-Einstein condensate quenched through a quantum phase transition. Using an off-resonant microwave field coupling the $F=1$ and $F=2$ atomic hyperfine levels, we rapidly switched the quadratic energy shift $q$ from positive to negative values. At $q=0$, the system undergoes a …