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Invalidity of Classes of Approximated Hall Effect Calculations

P. Ao
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Abstract

In this comment, I point out a number of approximated derivations for the effective equation of motion, now been applied to d-wave superconductors by Kopnin and Volovik are invalid. The major error in those approximated derivations is the inappropriate use of the relaxation time approximation in force-force correlation functions, or in force balance equations, or in similar variations. This approximation is wrong and unnecessary.

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P. Ao. 1998-06-04. Invalidity of Classes of Approximated Hall Effect Calculations. https://doi.org/10.1103/physrevlett.80.5025

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