Anisotropic Wigner crystal phases of two-dimensional electrons in high magnetic fields

We study the collective states formed by a two-dimensional electron gas in the presence of a perpendicular magnetic field. We numerically solve the static (time-independent) Hartree-Fock (HF) equations projected onto a given Landau level of index $n\geq 2$. We find that a triangular isotropic Wigner crystal (WC) is favored at small values of the partial filling factor $\nu^*$, but that at higher values of $\nu^*$ an anisotropic triangular WC becomes energetically more favorable. This anisotropic WC has a channel-like structure and can be viewed as a periodic arrangement of one-dimensional stacks of electron guiding centers that is reminiscent of the stripe state. Our results indicate that this ``striped" state is the ground state of the system over a wider region of partial filling factors than predicted within previous HF treatments.