Orbital coupled dipolar fermions in an asymmetric optical ladder

  title={Orbital coupled dipolar fermions in an asymmetric optical ladder},
  author={Xiaopeng Li and W. Vincent Liu},
  journal={Physical Review A},
We study a quantum ladder of interacting fermions with coupled s and p orbitals. Such a model describes dipolar molecules or atoms loaded into a double-well optical lattice, dipole moments being aligned by an external field. The two orbital components have distinct hoppings. The tunneling between them is equivalent to a partial Rashba spin-orbital coupling when the orbital space (s, p) is identified as spanned by pseudo-spin 1/2 states. A rich phase diagram, including incommensurate orbital… 

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