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arXiv · 1811.06104

Supersymmetry in an interacting Majorana model on the kagome lattice

Chengshu Li·Étienne Lantagne-Hurtubise·Marcel Franz
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Abstract

We construct a supersymmetric model of interacting Majorana fermions on the kagome lattice. In the infinite-coupling limit, the model exhibits an extensively degenerate ground state manifold separated in two topological sectors, in addition to two parity supersectors. An exact solution for thin-torus geometries allows us to analytically construct the entire zero-energy ground state manifold. Upon inclusion of hopping terms with energy scale $g$, the supersymmetry is spontaneously broken with the ground state energy density scaling as $g^4$. We also briefly discuss the non-interacting limit of the model, which exhibits a zero-energy flat band and Majorana Chern bands.

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Chengshu Li, Étienne Lantagne-Hurtubise, Marcel Franz. 2019-11-28. Supersymmetry in an interacting Majorana model on the kagome lattice. https://doi.org/10.1103/physrevb.100.195146

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