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تسجيل مستخدم جديدElectron currents from temporal gradients in tilted Dirac cone materials: Electric energy enabled by spacetime geometry
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Tilted Dirac/Weyl fermions admit a geometric description in terms of an effective spacetime metric. Using this metric, we formulate the hydrodynamics theory for tilted Dirac/Weyl materials in $d+1$ spacetime dimensions. We find that the mingling of spacetime through the off-diagonal components of the metric gives rise to: (i) heat and electric currents proportional to the {em temporal} gradient of temperature, $partial_t T$ and (ii) a non-zero Hall condductance $sigma^{ij}propto zeta^izeta^i$ where $zeta^j$ parametrizes the tilt in $j$th space direction. The finding (i) above suggests that naturally available sources of $partial_t T$ in hot deserts can serve as new concept for the extraction of electricity from the spacetime geometry. We find a further tilt-induced non-Drude contribution to conductivity which can be experimentally disentangles from the usual Drude pole.
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