CeRu ₂Al ₁₀: Anomalous magnetic ordering and its field stability

The intermetallic compound CeRu ₂Al ₁₀ orders in a new crystal structure type that is cage-like on account of its peculiar atomic arrangement and large interatomic distances-especially concerning the environment of the rare-earth element Ce. In previous work we showed that anomalous thermal, electronic, and magnetic properties of this compound coalesce into a phase transition at T ^*=27 K, which is exceptionally high for a cerium intermetallic compound. T ^* has been characterized through various temperature-dependent properties which suggest a multi-parameter nature of the ordering at T ^*. Here we report on continued investigations into this compound and focus in particular on the response to applied magnetic fields. Whereas transport properties in the ordered region are receptive to magnetic fields, the transition itself turns out to be more robust and is insensitive to static fields up to 14 T.