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arXiv · 1705.02799

$2π$-flux loop semimetals

Linhu Li·Stefano Chesi·Chuanhao Yin·Shu Chen
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Abstract

We introduce a model of $2π$-flux loop semimetals which holds nodal loops described by a winding number $ν=2$. By adding some extra terms, this model can be transformed into a recently discovered Hopf-link semimetal, and the symmetries distinguishing these two phases are studied. We also propose a simpler physical implementation of $2π$-flux loops and of the Hopf-link semimetals which only involves nearest-neighbor hoppings, although in the presence of spin-orbit interaction. Finally, we investigate the Floquet properties of the $2π$-flux loop, and find that such a loop may be driven into two separated $π$-flux loops or four Weyl points by light with circular polarization in certain directions.

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Linhu Li, Stefano Chesi, Chuanhao Yin, Shu Chen. 2017-05-08. $2π$-flux loop semimetals. https://doi.org/10.1103/physrevb.96.081116

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