Magnetoresistance, noise properties and the Koshino-Taylor effect in the quasi-1D oxide KRu ₄O ₈

The low-temperature electronic and galvanomagnetic transport properties of the low-dimensional oxide KRu ₄O ₈ are experimentally considered. A quadratic temperature variation of the resistivity is observed to be proportional to the residual resistivity. It shows the role of inelastic electron scattering against impurities, i.e. a large Koshino-Taylor effect, rather than a consequence of strong electronic correlations. In the same temperature range, the Kohler rule is not fulfilled. The resistance noise increases also sharply, possibly due to a strong coupling of carriers with lattice fluctuations in this low-dimensional compound.