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We present a detailed study of the electronic transport properties on a single crystalline specimen of the moderately disordered heavy fermion system URh2Ge2. For this material, we find glassy electronic transport in a single crystalline compound. We derive the temperature dependence of the electrical conductivity and establish metallicity by means of optical conductivity and Hall effect measurements. The overall behavior of the electronic transport properties closely resembles that of metallic glasses, with at low temperatures an additional minor spin disorder contribution. We argue that this glassy electronic behavior in a crystalline compound reflects the enhancement of disorder effects as consequence of strong electronic correlations.

We present a detailed study on the (magneto)transport properties of as-cast and heat treated material UCu4Pd. We find a pronounced sample dependence of the resistivity ρ of as-cast samples, and reproduce the annealing dependence of ρ. In our study of the Hall effect we determine a metallic carrier density for all samples, and a temperature dependence of the Hall constant which is inconsistent with the Skew scattering prediction. The magnetoresistive response is very small and characteristic for spin disorder scattering, suggesting that overall the resistivity is controlled mostly by nonmagnetic scattering processes. We discuss possible sources for the temperature and field dependence of the transport properties, in particular with respect to quantum criticality and electronic localization effects.

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We present a susceptibility study on single crystalline UPt2Si2. For this material, which orders antiferromagnetically below TN=31 K, we observe irreversibility in susceptibility runs performed in field cooled and zero field cooled modes, respectively. The irreversibility exhibits pronounced anisotropy. While along the c axis it sets in above TN, i.e., at Tirr≃36 K, along the a axis we find a much lower Tirr∼10 K. The observation of magnetic irreversibility indicates the presence of crystallographic disorder in this single crystalline, stoichiometric compound. We discuss possible sources of the crystallographic disorder and unusual irreversibility behavior of this compound.