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arXiv · 1204.6682

Simplex solids in SU(N) Heisenberg models on the kagome and checkerboard lattices

Philippe Corboz·Karlo Penc·Frederic Mila·Andreas M. Laeuchli
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Abstract

We present a numerical study of the SU(N) Heisenberg model with the fundamental representation at each site for the kagome lattice (for N=3) and the checkerboard lattice (for N=4), which are the line graphs of the honeycomb and square lattices and thus belong to the class of bisimplex lattices. Using infinite projected entangled-pair states (iPEPS) and exact diagonalizations, we show that in both cases the ground state is a simplex solid state with a two-fold ground state degeneracy, in which the N spins belonging to a simplex (i.e. a complete graph) form a singlet. Theses states can be seen as generalizations of valence bond solid states known to be stabilized in certain SU(2) spin models.

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Philippe Corboz, Karlo Penc, Frederic Mila, Andreas M. Laeuchli. 2012-04-30. Simplex solids in SU(N) Heisenberg models on the kagome and checkerboard lattices. https://doi.org/10.1103/physrevb.86.041106

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