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Optical signatures of Dirac nodal lines in NbAs2.

ABSTRACT: 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 of [Formula: see text] where the spin-orbit coupling (SOC) triggers energy gaps along the nodal lines. These gaps manifest as sharp steps in the optical conductivity spectra [Formula: see text] This behavior is followed by the linear power-law scaling of [Formula: see text] 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 of [Formula: see text].

SUBMITTER: Shao Y

PROVIDER: S-EPMC6347680 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Optical signatures of Dirac nodal lines in NbAs2.

Shao Yinming Y Sun Zhiyuan Z Wang Ying Y Xu Chenchao C Sankar Raman R Breindel Alexander J AJ Cao Chao C Fogler Michael M MM Millis Andrew J AJ Chou Fangcheng F Li Zhiqiang Z Timusk Thomas T Maple M Brian MB Basov D N DN

Proceedings of the National Academy of Sciences of the United States of America 20181217 4

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 of [Formula: see text] where the spin-orbit coupling (SOC) triggers energy gaps along the nodal lines. These gaps manifest as sharp steps in the optical conductivity spectra [Formula: see text] This behavior is followed by the li ...[more]

PMID: 30559211

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