  We derive an exact solution to the problem of spin snake states induced in a
nonhomogeneous magnetic field by a combined action of the Rashba spin-orbit and
Zeeman fields. In an antisymmetric magnetic field the spin snake states are
nonlocal composite particles, originating from spatially separated entangled
spins. Adding an external homogeneous magnetic field breaks the spin-parity
symmetry gapping out the spectral branches, which results in a regular beating
pattern of the spin current. These new phenomena in a helical liquid of snake
states are proposed for an experimental realization.
