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arXiv · 1202.0291

Fractionalized topological insulators from frustrated spin models in three dimensions

Subhro Bhattacharjee·Yong Baek Kim·Sung-Sik Lee·Dung-Hai Lee
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Abstract

We present a theory of three dimensional fractionalized topological insulators in the form of U(1) spin liquids with gapped fermionic spinons in the bulk and topologically protected gapless spinon surface states. Starting from a spin-1/2 model on a pyrochlore lattice, with frustrated antiferromagnetic and ferromagnetic exchange interactions, we show that decomposition of the latter interactions, within slave-fermion representation of the spins, can naturally give rise to an emergent spin-orbit coupling for the spinons. This stabilizes a fractionalized topological insulators which also have bulk bond spin-nematic order. Finally, we describe the low energy properties of these states.

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Subhro Bhattacharjee, Yong Baek Kim, Sung-Sik Lee, Dung-Hai Lee. 2012-02-01. Fractionalized topological insulators from frustrated spin models in three dimensions. https://doi.org/10.1103/physrevb.85.224428

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