Temperature Dependence of Transport Coe cients in
نویسنده
چکیده
We apply the mu n-tin e ective medium approximation to calculate the temperature dependence of the resistivity and thermopower of amorphous and liquid metals. The results show unambiguously that a large resistivity is accompanied by a negative temperature coe cient, in agreement with the experimental situation. This behavior is shown to result from a pseudo-gap which opens in the one-particle spectrum due to strong scattering at the quasi zone boundary and which tends to close under an increase in temperature. In turn the thermopower is found to have non-trivial density and temperature dependences. 2
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