Abstract
We report on the anomalous behavior of the complex conductivity of BaFe$_{2}$As$_{2}$, which is related to the Dirac cone, in the terahertz (THz)-frequency region. Above the spin-density-wave (SDW) transition temperature, the conductivity spectra follow the Drude model. In the SDW state, the imaginary part of the complex conductivity, $\sigma_2$, is suppressed in comparison to that expected according to the Drude model. The real part, $\sigma_1$, exhibits nearly Drude-like behavior. This behavior (i.e., almost no changes in $\sigma_1$ and the depression of $\sigma_2$) can be regarded as the addition of extra conductivity without any dissipations in the Drude-type conductivity. The origin of this ultralow-dissipative conductivity is found to be due to conductivity contribution from quasiparticles within the Dirac cone. In other words, we are able to observe the dynamics of Dirac fermions through the conductivity spectra of BaFe$_2$As$_2$, clearly and directly.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
