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arXiv · 0710.0215

Correlation effects on magnetic frustration in the triangular-lattice Hubbard model

Saptarshi Ghosh·Avinash Singh
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Abstract

Evolution of the magnetic response function in the triangular-lattice Hubbard model is studied with interaction strength within a systematic inverse-degeneracy expansion scheme which incorporates self-energy and vertex corrections and explicitly preserves the spin-rotation symmetry. It is shown that at half filling the response function goes through a nearly dispersionless regime around K for intermediate coupling strength, before undergoing an inversion at strong coupling, resulting in maximum response at the K point, consistent with the expected 120^o AF instability. Effects of finite hole/electron doping on the magnetic response function are also examined.

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Saptarshi Ghosh, Avinash Singh. 2007-10-01. Correlation effects on magnetic frustration in the triangular-lattice Hubbard model. https://doi.org/10.1103/physrevb.77.094430

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