Ising antiferromagnet with ultracold bosonic mixtures confined in a   harmonic trap
  We present accurate results based on Quantum Monte Carlo simulations of two-component bosonic systems on a square lattice and in the presence of an external harmonic confinement. Starting from hopping parameters and interaction strengths which stabilize the Ising antiferromagnetic phase in the homogeneous case and at half integer filling factor, we study how the presence of the harmonic confinement challenge the realization of such phase. We consider realistic trapping frequencies and number of particles, and establish under which conditions, i.e. total number of particles and population imbalance, the antiferromagnetic phase can be observed in the trap. 
Marco Guglielmino, Vittorio Penna, Barbara Capogrosso-Sansone
cond-mat.quant-gas