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تسجيل مستخدم جديدEvidence for Undoped Weyl Semimetal Charge Transport in $Y_{2}Ir_{2}O_{7}$
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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 models range of applicability. In particular, the behavior extends into the low-temperature, high-resistivity region where the Ioffe-Regel parameter, $k_{T} ell ll 2pi$. 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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