  We generate a crystal of skyrmions in two dimensions using a Heisenberg
Hamiltonian including the ferromagnetic interaction J, the
Dzyaloshinskii-Moriya interaction D, and an applied magnetic field H. The
ground state (GS) is determined by minimizing the interaction energy. We show
that the GS is a skyrmion crystal in a region of (D, H). The stability of this
skyrmion crystalline phase at finite temperatures is shown by a study of the
time-dependence of the order parameter using Monte Carlo simulations. We
observe that the relaxation is very slow and follows a stretched exponential
law. The skyrmion crystal phase is shown to undergo a transition to the
paramagnetic state at a finite temperature.
