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Violation of Kohler's rule by the magnetoresistance of a quasi-two-dimensional organic metal

Ross H. McKenzie·J. S. Qualls·S. Y. Han·J. S. Brooks
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Abstract

The interlayer magnetoresistance of the quasi-two-dimensional metal $α$-(BEDT-TTF)$_2$KHg(SCN)$_4$ is considered. In the temperature range from 0.5 to 10 K and for fields up to 10 tesla the magnetoresistance has a stronger temperature dependence than the zero-field resistance. Consequently Kohler's rule is not obeyed for any range of temperatures or fields. This means that the magnetoresistance cannot be described in terms of semiclassical transport on a single Fermi surface with a single scattering time. Possible explanations for the violations of Kohler's rule are considered, both within the framework of semi-classical transport theory and involving incoherent interlayer transport. The issues considered are similar to those raised by the magnetotransport of the cuprate superconductors.

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Ross H. McKenzie, J. S. Qualls, S. Y. Han, J. S. Brooks. 1998-03-04. Violation of Kohler's rule by the magnetoresistance of a quasi-two-dimensional organic metal. https://doi.org/10.1103/physrevb.57.11854

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