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arXiv · 1411.7379

Weyl spin liquids

Maria Hermanns·Kevin O'Brien·Simon Trebst
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Abstract

The fractionalization of quantum numbers in interacting quantum-many body systems is a central motif in condensed matter physics with prominent examples including the fractionalization of the electron in quantum Hall liquids or the emergence of magnetic monopoles in spin-ice materials. Here we discuss the fractionalization of magnetic moments in three-dimensional Kitaev models into Majorana fermions (and a $\mathbb Z_2$ gauge field) and their emergent collective behavior. We analytically demonstrate that the Majorana fermions form a Weyl superconductor for the Kitaev model on the recently synthesized hyperhoneycomb structure of $β$-Li$_2$IrO$_3$ when applying a magnetic field. We characterize the topologically protected bulk and surface features of this state, which we dub a Weyl spin liquid, including thermodynamic and transport signatures.

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Maria Hermanns, Kevin O'Brien, Simon Trebst. 2015-04-15. Weyl spin liquids. https://doi.org/10.1103/physrevlett.114.157202

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