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arXiv · 1705.00567

Anisotropic plasmons, Friedel oscillations and dynamical screening in $8-Pmmn$ borophene

Krishanu Sadhukan·Amit Agarwal
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Abstract

$8-Pmmn$ borophene is a polymorph of borophene which hosts an anisotropic tilted Dirac cone. Using a low energy effective Hamiltonian for borophene, we analytically calculate the density-density response function of borophene and study its anisotropic plasmon dispersion and screening properties. We find that the anisotropic plasmon mode in $8-Pmmn$ borophene, remains undamped for higher energies along the mirror symmetry direction. The friedel oscillation in borophene is found to decay as $r^{-3}$ in the large $r$ limit, with both the amplitude as well as the periodicity of the Friedel oscillations being anisotropic.

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Krishanu Sadhukan, Amit Agarwal. 2017-05-01. Anisotropic plasmons, Friedel oscillations and dynamical screening in $8-Pmmn$ borophene. https://doi.org/10.1103/physrevb.96.035410

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