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arXiv · 1207.4058

Schwinger boson mean field theory: numerics for the energy landscape and gauge excitations in two-dimensional antiferromagnets

Grégoire Misguich
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Abstract

We perform some systematic numerical search for Schwinger boson mean field states on square and triangular lattice clusters. We look for possible inhomogeneous ground states as well as low-energy excited saddle points. The spectrum of the Hessian is also computed for each solution. On the square lattice we find gapless U(1) gauge modes in the non-magnetic phase. In the Z_2 liquid phase of the triangular lattice we identify the topological degeneracy as well as vison states.

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Grégoire Misguich. 2012-12-11. Schwinger boson mean field theory: numerics for the energy landscape and gauge excitations in two-dimensional antiferromagnets. https://doi.org/10.1103/physrevb.86.245132

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