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arXiv · 1203.5776

Broken translational symmetry in an emergent paramagnetic phase of graphene

Gia-Wei Chern·Rafael M. Fernandes·Rahul Nandkishore·Andrey V. Chubukov
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Abstract

We show that the spin-density wave state on the partially filled honeycomb and triangular lattices is preempted by a paramagnetic phase that breaks an emergent Z_4 symmetry of the system, associated with the four inequivalent arrangements of spins in the quadrupled unit cell. Unlike other emergent paramagnetic phases in itinerant and localized-spin systems, this state preserves the rotational symmetry of the lattice but breaks its translational symmetry, giving rise to a super-lattice structure that can be detected by scanning tunneling microscopy. This emergent phase also has distinctive signatures in the magnetic spectrum that can be probed experimentally.

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Gia-Wei Chern, Rafael M. Fernandes, Rahul Nandkishore, Andrey V. Chubukov. 2012-03-26. Broken translational symmetry in an emergent paramagnetic phase of graphene. https://doi.org/10.1103/physrevb.86.115443

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