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Title: Optical signatures of Dirac nodal lines in NbAs 2

Using polarized optical and magneto-optical spectroscopy, we have demonstrated universal aspects of electrodynamics associated with Dirac nodal lines that are found in several classes of unconventional intermetallic compounds. We investigated anisotropic electrodynamics ofNbAs2where the spin-orbit coupling (SOC) triggers energy gaps along the nodal lines. These gaps manifest as sharp steps in the optical conductivity spectraσ1(ω). This behavior is followed by the linear power-law scaling ofσ1(ω)at higher frequencies, consistent with our theoretical analysis for dispersive Dirac nodal lines. Magneto-optics data affirm the dominant role of nodal lines in the electrodynamics ofNbAs2.

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Publication Date:
Journal Name:
Proceedings of the National Academy of Sciences
Page Range or eLocation-ID:
p. 1168-1173
Proceedings of the National Academy of Sciences
Sponsoring Org:
National Science Foundation
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