Optical conductivity of anisotropic Dirac semimetals: The relaxation-time approximation

Scientific paper - Original scientific paper

• Author: Ivan Kupčić
• Author: J. Kordić
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

The current-dipole conductivity formula for doped three-dimensional Dirac semimetals is derived by using a modified gauge-invariant tight-binding approach. In a heavily doped regime, the effective number of charge carriers neff alpha alpha in the Drude contribution is found to be by a factor of 4 larger than the nominal electron concentration n. However, its structure is the same as in standard Fermi liquid theory. In a lightly doped regime, on the other hand, the ratio neff alpha alpha/n is much larger, with much more complex structure of neff alpha alpha. It is shown that the dc resistivity and reflectivity date measured in two TlBiSSe samples can be easily understood, even in the relaxation-time approximation, provided that finite quasiparticle lifetime effects in the momentum distribution functions are properly taken into account.

• Keywords (english): Dirac semimetals, optical conductivity, relaxation-time approximation
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical Review B
• Numbering: vol. 109, no. 4, 045426
• p-ISSN: 2469-9950
• e-ISSN: 2469-9969
• DOI: https://doi.org/10.1103/PhysRevB.109.045426
• URN:NBN: urn:nbn:hr:217:192736
• Publication: 2024
• Document URL: https://link.aps.org/doi/10.1103/PhysRevB.109.045426
• Type of resource: Text
• Access conditions: Open access
• Public note: © 2024 American Physical Society. Received 19 October 2023. Revised 18 December 2023. Accepted 8 January 2024. Published 19 January 2024.
• Created on: 2024-07-25 11:43:56