MAGNETIC PROPERTIES OF DYAS AND DYP (001) FILMS

The magnetic properties of two single crystal (001) films of DyP and DyAs have been investigated at temperatures between 2 and 300 K and at fields up to 5 T using SQUID magnetometry. The films were grown epitaxially in the simple NaCl structure on (001) GaAs substrates using molecular beam epitaxy techniques. The phosphide compound exhibits ferromagnetic-like order below ∼9 K. The ordered phase appears to have 90° spin alignments, a suppressed saturation moment (∼1.0μB), and a large magnetic anisotropy. In contrast, the arsenide develops an antiferromagnetic-like correlation below ∼6 K, with a much lower anisotropy and a higher moment (∼2.8μB) than that of the phosphide. Above the ordering transitions, the two samples exhibit paramagnetism with paramagnetic moments of 4.5 and 7.8μB for the DyP and the DyAs sample, respectively. The observed behavior is consistent with the presence of strong crystal field interactions. Experiments have been proposed to further explore these effects.