Anisotropies in critical currents and transition fields have been measured for sputter-deposited superconducting films. For thicker films, the peak at θ = 90° in the Ic-θ characteristics is strongly marked. As the film thickness decreases, the peak at θ = 90° tends to reduce, and finally disappears in the film thinner than the critical thickness. Furthermore, the transition fields Ht have been found to be anisotropic with respect to the applied field direction θ. The marked peak at θ = 90° in the Ht-θ characteristics is found for films thicker than the critical thickness.

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A resistance anomaly of very thin Nb–Si films is reported. The anomaly is characterized by a sudden drop in the resistance by a factor of ∼103 at a temperature (T D ) of ∼180K without any application of pressure. The lower resistance-state (∼zero Ω) is constant to 4.2K so far as we measured. T D depends on measuring current and on magnetic fields. The anomaly has properties very similar to those of CuCl under high pressure.

HoAuGe was prepared from the elements by arc melting and subsequent annealing at 1070 K. Its crystal structure was refined from single-crystal xray diffractometer data: a = 440.10(5) pm, c = 723.26(9) pm, V = 0.1213(1) nm 3 , wR2 = 0.0640, 225 F 2 -values and ten variables. The nuclear structure was confirmed by neutron powder diffraction. HoAuGe adopts the NdPtSb-type structure. The gold and germanium atoms form two-dimensional infinite [AuGe] polyanions with intralayer Au-Ge distances of 260.5 pm, while the interlayer Au-Ge distances of 304.1 pm are much longer. The polyanions are separated by the holmium ions. Magnetic susceptibility, specific heat capacity and neutron diffraction measurements reveal antiferromagnetic ordering at T N = 5.6(2) K with further magnetic reordering at T 1 = 3.5(2) K and T 2 = 2.4(2) K. At higher temperatures Curie-Weiss behaviour is observed with µ exp eff = 10.2(2) µ B and p = 0(1) K. From the magnetic specific heat a fourfold-degenerate ground state is found. The magnetic structure at 1.3 K is described by the propagation vector k = (1/2, 0, 0) with the Ho spins oriented within the bc-plane. As the temperature increases towards T N , the magnetic structure becomes incommensurate, which accounts for the observed additional transitions below T N .

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