Superexchange-mediated magnetization dynamics with ultracold alkaline-earth atoms in an optical lattice
Zhu Shaobing1, 2, Qian Jun1, Wang Yuzhu1, †
       

(color online) (a) Schematic diagram of the superexchange and inter-orbital spin-exchange interactions. The atoms are independently trapped in the shallow (deep) superlattice, whose nuclear spin states are marked by and . The superexchange process (green arrow) happens between AFM states ( ) via virtual tunneling (black dashed arrows), while two-orbital spin-exchange interaction (red arrows) couples with the magnetic state . (b) Time evolution of the spin imbalance Ngz of the g atoms (black) and the population of the state (blue) for a small magnetic field (the resulting differential Zeeman shift can be ignored) and the initial state . The envelope of Ngz is given by (red). The collapse and revival happen at and , respectively. (c) Energy levels of the perturbation model (left) and the eigenstates (right). . are the coupling matrix elements. δ is the energy shift. The red solid and blue dashed arrows indicate the near-resonant coupling and far-off-resonant coupling, respectively. (d) Time evolution of the spin-imbalance of g atoms with (black line). The envelope (red solid) corresponds to . The parameters are , , in panels (b) and (d).