  Stripe states in multilayer systems with perpendicular polarization are
investigated by analytical calculations within a general continuum approach,
applicable to ferromagnetic, ferroelectric, or ferroelastic nanoscale
superlattices. The competition between the long-range depolarization effect and
short-range interlayer couplings can stabilize monodomain states and unusual
stripe phase ground states with antiparallel polarization in adjacent layers.
Geometric parameters of stable stripe domain states and the phase transitions
lines between single domain states, aligned and antialigned stripe states have
been derived. The theory is applied to analyze multidomain states and phase
transitions in antiferromagnetically coupled multilayers [CoPt]/Ru.
