Evolution and decay of an Alice ring in a spinor Bose-Einstein condensate

We use first-principles-derived numerical simulations to investigate the long-time evolution of a half-quantum vortex ring, an Alice arising from decay dynamics isolated monopole in polar phase dilute spin-1 Bose-Einstein condensate. In particular, we study lifetime and characteristics ring under different experimentally relevant conditions. observe that, $^{87}\mathrm{Rb}$ condensate with homogeneous external magnetic field, well-centered may survive for over 160 ms, that during its it can contract back into monopole, which again converts ring. Interestingly, notice additional opposite topological charge, emerge within condensate, leading coexistence two rings same cloud. Shortly after this coexistence, original breaks line-like defect referred as string. find location initial correlates winding direction scalar produced phenomenon utilize create charges directions. Such created anti-Alice naturally annihilate each other subsequent evolution.