Evidence for Undoped Weyl Semimetal Charge Transport in $Y_{2}Ir_{2}O_{7}$

P. G. LaBarre; L. Dong; J. Trinh; T. Siegrist; A. P. Ramirez

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arXiv · 1808.07583

Evidence for Undoped Weyl Semimetal Charge Transport in $Y_{2}Ir_{2}O_{7}$

P. G. LaBarre·L. Dong·J. Trinh·T. Siegrist·A. P. Ramirez

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Abstract

Weyl fermions scattering from a random Coulomb potential are predicted to exhibit resistivity versus temperature $\rho \space \alpha \space T^{-4}$ in a single particle model. Here we show that, in closed environment-grown polycrystalline samples of $Y_{2}Ir_{2}O_{7}$, $\rho = \rho_{0} T^{-4}$ over four orders of magnitude in $\rho$. While the measured prefactor, $\rho_{0}$, is obtained from the model using reasonable materials parameters, the $T^{-4}$ behavior extends far beyond the model's range of applicability. In particular, the behavior extends into the low-temperature, high-resistivity region where the Ioffe-Regel parameter, $k_{T} \ell \ll 2\pi$. Strong on-site Coulomb correlations, instrumental for predicting a Weyl semimetal state in $Y_{2}Ir_{2}O_{7}$, are the possible origin of such "bad" Weyl semimetal behavior.

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P. G. LaBarre, L. Dong, J. Trinh, T. Siegrist, A. P. Ramirez. 2018-08-22. Evidence for Undoped Weyl Semimetal Charge Transport in $Y_{2}Ir_{2}O_{7}$. https://arxiv.org/abs/1808.07583

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