The current-voltage characteristic has been measured for a probe/Langmuir–Blodgett (LB) film/metal structure with the scanning tunneling microscope (STM). The rapid increase of current and substantial increase in conductance have been found when a critical positive voltage was applied to the probe. A bright spot in the STM image has been observed at the position where the increase in the conductance occurred. The changes in the STM images are attributed to the change in the conductance of LB films themselves rather than the surface topography, and may be associated with the switching phenomena in LB films.

This paper has reported on the performance, in the range between room and liquid nitrogen temperatures, of a Gouy-type magnetic balance, which had been constructed for absolute measurements of the magnetic susceptibility of paramagnetic salts. As a magnetic field, we used a highly homogeneous permanent magnet which was easily movable by hand. Therefore, precise measurement of the susceptibily is possible. With this balance, the susceptibility of 10−5c.g.s. units was measurable within a range of error of 5%.

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We have synthesized polycrystalline Ce x La 1−x B 2 C 2 samples and measured the temperature dependence of the low-field magnetization, ac susceptibility and specific heat. As the Ce concentration x decreases, the Néel temperature T N decreases linearly for x 0.80. However, the dependence on the concentration x of the transition temperature changes slope at x ∼ 0.75. Spin-glass transitions are observed for 0.4 x 0.75. The origin of the spin-glass behaviour will be discussed.