Dynamic Order-Reversal Transition in a Parametrically Driven Cold Atomic System

We experimentally demonstrate the reversal transition of the order in a parametrically driven cold atomic system which shows ideal mean-field symmetry-breaking transition, by the application of the pulsed additional bias-field opposite to the pre-existing order. The strength $h_{0}$ and the duration \textit{$\Delta $t} of pulse are the control parameters of the reversal transition. We obtain the phase boundary of the transition and there is critical slowing down behavior near the phase boundary via diverging relaxation time.