  We investigate the influence of the external fields on the stability of spin
helix states in a XXZ Heisenberg model. Exact diagonalization on finite system
shows that random transverse fields in x and y directions drive the transition
from integrability to nonintegrability. It results in the fast decay of a
static helix state, which is the eigenstate of an unperturbed XXZ Heisenberg
model. However, in the presence of uniform z field, the static helix state
becomes a dynamic helix state with a relatively long life as a quantum scar
state.
