Floquet engineering of topological semimetals with bicircularly polarized light

Maitri Ganguli; Aneek Jana; Awadhesh Narayan

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arXiv · 2410.05158

Floquet engineering of topological semimetals with bicircularly polarized light

Maitri Ganguli·Aneek Jana·Awadhesh Narayan

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Abstract

We study the effect of illumination of bicircularly polarized light (BCL) on topological semimetals, namely multifold fermion and line-node semimetals. We demonstrate, by means of both low-energy and lattice models, that the band-structures of both multifold fermions and line-node semimetal exhibit rich features with BCL illumination. For multifold fermions, we show that if the relative amplitude, $r$, between the two frequency components of the BCL is related to the relative frequency, $\eta$, in such a way that $r^2 = \eta$, then the band touching points remain unchanged without any shift or band gap opening for any choice of the material-dependent parameters. For other choices of the BCL parameters, we find both gapped phases as well as gapless phases with shifted band touching points. Line-node semimetals also exhibit diverse phases, ranging from protected line-nodes under illumination to point nodes, by tuning the BCL parameters $r$ and $\eta$. Overall, our analytical and numerical results establish BCL as a versatile tool for obtaining tunable topological phases.

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Maitri Ganguli, Aneek Jana, Awadhesh Narayan. 2024-10-07. Floquet engineering of topological semimetals with bicircularly polarized light. https://arxiv.org/abs/2410.05158

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