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arXiv · 1502.04515

Two-leg SU(2n) spin ladder: A low-energy effective field theory approach

P. Lecheminant·A. M. Tsvelik
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Abstract

We present a field theory analysis of a model of two SU(2n)-invariant magnetic chains coupled by a generic interaction preserving time reversal and inversion symmetry. Contrary to the SU(2)-invariant case the zero-temperature phase diagram of such two-leg spin ladder does not contain topological phases. Only generalized Valence Bond Solid phases are stabilized when n>1 with different wave vectors and ground-state degeneracies. In particular, we find a phase which is made of a cluster of 2n spins put in an SU(2n) singlet state. For n=3, this cluster phase is relevant to ytterbium ultracold atoms, with an emergent SU(6) symmetry, loaded in double well optical lattice.

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P. Lecheminant, A. M. Tsvelik. 2015-02-18. Two-leg SU(2n) spin ladder: A low-energy effective field theory approach. https://doi.org/10.1103/physrevb.91.174407

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