  Spatially-periodic patterns are studied in nonlocally coupled
Gross-Pitaevskii equation. We show first that spatially periodic patterns
appear in a model with the dipole-dipole interaction. Next, we study a model
with a finite-range coupling, and show that a repulsively coupled system is
closely related with an attractively coupled system and its soliton solution
becomes a building block of the spatially-periodic structure. That is, the
spatially-periodic structure can be interpreted as a soliton lattice. An
approximate form of the soliton is given by a variational method. Furthermore,
the effects of the rotating harmonic potential and spin-orbit coupling are
numerically studied.
