Pseudo-spin order of Wigner crystals in multi-valley electron gases

Abstract

We study multi-valley electron gases in the low density ($r_s\gg 1$) limit. Here the ground-state is always a Wigner crystal (WC), with additional pseudo-spin order where the pseudo-spins are related to valley occupancies. Depending on the symmetries of the host semiconductor and the values of the parameters such as the anisotropy of the effective mass tensors, we find a striped or chiral pseudo-spin antiferromagnet, or a time-reversal symmetry breaking orbital loop-current ordered pseudo-spin ferromagnet. Our theory applies to the recently-discovered WC states in AlAs and in mono and bilayer transition metal dichalcogenides. We identify a set of interesting electronic liquid crystalline phases that could arise by continuous quantum melting of such WCs.

21 pages (including Appendices), 11 figures

References in corpus (1)

• Observation of Spontaneous Ferromagnetism in a Two-Dimensional Electron System

Cited by in corpus (8)

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• Chiral Wigner crystal phases induced by Berry curvature
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• Magnetism of the Bilayer Wigner Crystal
• Exchange Interactions of a Wigner Crystal in a Magnetic Field and Berry Curvature: Multi-Particle Tunneling through Complex Trajectories
• Spin-triplet paired Wigner crystal stabilized by quantum geometry