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arXiv · 1904.10758

Optical conductivity of triple point fermions

Alireza Habibi·Tohid Farajollahpour·S. A. Jafari
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Abstract

As a low-energy effective theory on non-symmorphic lattices, we consider a generic triple point fermion Hamiltonian which is parameterized by an angular parameter $\lambda$. We find strong $\lambda$ dependence in both Drude and interband optical absorption of these systems. The deviation of the $T^2$ coefficient of the Drude weight from Dirac/Weyl fermions can be used as a quick way to optically distinguish the triple point degeneracies from the Dirac/Weyl degeneracies. At the particular $\lambda=\pi/6$ point, we find that the "helicity" reversal optical transition matrix element is identically zero. But deviating from this point, the helicity reversal emerges as an absorption channel.

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Alireza Habibi, Tohid Farajollahpour, S. A. Jafari. 2019-04-24. Optical conductivity of triple point fermions. https://doi.org/10.1088/1361-648x%2Fabd739

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