We report on the low-temperature properties of the ternary europium pnictide EuZn 2 Sb 2 . Bulk properties were characterized in terms of the electrical resistivity, magnetoresistance, Hall effect, magnetization, specific heat, and thermal expansion. The data are consistent with an antiferromagnetic order of divalent europium below T N = 13.3 K. The phase transition at T N is clearly visible in all properties measured. The magnetic field-temperature phase diagram was derived from the magnetization, specific heat, and resistivity. For the field parallel and perpendicular to the trigonal c axis the antiferromagnetism is suppressed above B ʈ Ϸ 4.7 T and B Ќ Ϸ 3.5 T, respectively. The critical exponent ␣ observed in the specific heat near T N is consistent with both the predictions of the three-dimensional ͑3D͒ XY as well as the 3D-Heisenberg model.

We measure the energy-dependent interface recombination parameters at the c-Si/Al2O3 interface using the frequency-dependent conductance technique. The hole capture cross section σp = (4 ± 3) × 10−16 cm2 is energy-independent, whereas the electron capture cross section σn shows a pronounced energy dependence and decreases from (7 ± 4) × 10−15 cm2 at midgap over two orders of magnitude toward the conduction band edge Ec. The capture cross section ratio at midgap is highly asymmetric with σn/σp = 5–70. The interface state density Dit is of the order of 1 × 1011 eV−1 cm−2 at midgap. Besides the main defect, a second type of defect with a capture cross section below 10−19 cm2 is resolved near the valence band edge. Numerical calculations of the injection-dependent effective surface recombination velocity using the measured interface recombination parameters show an excellent agreement with experimental data measured using the photoconductance technique.

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In Nb/Ag layers, the induced superconductivity in Ag by Nb gives rise to diamagnetic screening currents in the Ag layer well below the transition temperature of the superconductor. By investigating the position dependence of the individual diamagnetic transitions of Nb and Ag with a gradiometer in a nearly parallel magnetic field, we find that the screening of the Ag layer is remarkably different compared to the Nb layer. While for the Nb layer a strong out-of-plane contribution is observed due to the large demagnetization factor, such a contribution is absent for the Ag layer. This can be explained by the partial overscreening of the magnetic field, i.e. a reduced diamagnetic response of the Ag layer, as suggested by the theory for the clean limit.