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arXiv · 1205.0014

Non-Abelian SU(2) gauge fields through density-wave order and strain in graphene

Sarang Gopalakrishnan·Pouyan Ghaemi·Shinsei Ryu
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Abstract

Spatially varying strain patterns can qualitatively alter the electronic properties of graphene, acting as effective valley-dependent magnetic fields and giving rise to pseudo-Landau-level (PLL) quantization. Here, we show that the strain-induced magnetic field is one component of an SU(2) non-Abelian gauge field within the low-energy theory of graphene, and identify the other two components as period-3 charge-density waves. We show that these density-waves, if spatially varied, give rise to PLL quantization. We also argue that strain-induced magnetic fields can induce density-wave order in graphene, thus dynamically gapping out the lowest PLL; moreover, the ordering should generically be accompanied by dislocations. We discuss experimental signatures of these effects.

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Sarang Gopalakrishnan, Pouyan Ghaemi, Shinsei Ryu. 2012-04-30. Non-Abelian SU(2) gauge fields through density-wave order and strain in graphene. https://doi.org/10.1103/physrevb.86.081403

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