
A new class of materials known as socalled "bad metals" show transport properties not understandable using conventional transport theory. Their resistivities at high temperatures imply electron mean free paths less than an interatomic distance, and their infrared conductivity is not in agreement with conventional Drude theory. We are using SrRuO_{3} as a model system to study this phenomenon.
DC conductivity measurements on SrRuO_{3} films reveal some anomalous behavior. The resistance at high temperatures continues to rise linearly with temperature beyond the point where conventional theories are no longer applicable Measurements of the frequency dependent conductivity by infrared reflectivity and terahertz timedomain spectroscopy, show an analytic structure fundamentally different from that predicted by the standard theory of metals. The low temperature resistance incrased like T^{2}, as expected from electronelectron scattering. Residual resistivities achieved are comparable to the best single crystal values.
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