Macroscopic Degeneracy and Emergent Frustration in a Honeycomb Lattice Magnet

Abstract

Using a hybrid method based on fermionic diagonalization and classical Monte Carlo, we investigate the interplay between itinerant and localized spins, with competing double- and super-exchange interactions, on a honeycomb lattice. For moderate superexchange, a geometrically frustrated triangular lattice of hexagons forms spontaneously. For slightly larger superexchange a dimerized groundstate is stable that has macroscopic degeneracy. The presence of these states on a non-frustrated honeycomb lattice highlights a novel phenomenon in this itinerant electron system: emergent geometrical frustration and degeneracy.

4+ pages, 4 figures; published version

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Cited by in corpus (8)

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• Novel magnetic orderings in the kagome Kondo-lattice model
• Cluster Frustration in the Breathing Pyrochlore Magnet LiGaCr4S8
• New Microscopic Magnetic Hamiltonian for Exotic Spin Textures in Metals
• A platform for nanomagnetism - assembled ferromagnetic and antiferromagnetic dipolar tubes
• Spin Canting and Orbital Order in Spinel Vanadate Thin Films
• From Frustrated to Unfrustrated: Coupling two triangular-lattice itinerant Quantum Magnets
• Integer vs. half-integer spin on an approximate honeycomb lattice